A lot of young people seem to know exactly what they want out of life at an extremely young age. Unfortunately, I was not one of those people. I had no clue what I wanted to do for a living, where I saw myself settling one day, or what my actual values were. But, I did know I desperately wanted to fall in love and have the type of relationship people wrote poems and songs about.

So much about life seemed complicated, ugly, and frustrating. But I saw romantic, committed love as the one thing I would always be able to count on to be beautiful, easy, and meaningful — something that, once found, I’d always be able to turn to for comfort and solace. (Boy, did I have a lot to learn.)

I’d go on to spend most of my adult life suffering through one unsatisfying relationship after another. But since I was almost always the one ending things, it was hard to see my own role in what was happening. A first divorce while still in my 20s showed me just how much I had left to learn, but so did some of the challenges that came with my much-more-successful second marriage.

The thing is, love can be beautiful on a world-changing level and often is. But even good relationships come with challenges, learning curves, and reality checks. And you know what? Most of the more valuable lessons never show up in anyone’s rose-colored, chocolate-scented love poetry. Here are a few examples it took me until my 40s to finally get.

1. You fall in love with ideas, not people.

We all do it, even those of us who pride ourselves on accepting other people as they are. I used to get so mad at my partners for conceptualizing me — for painting this elaborate picture of who they thought I was or could become and falling in love with that instead of with the real me. It took me a while to realize I was doing the exact same thing to them, not because I’m a horrible person, but because it’s not possible to do anything else.

Genuinely getting to know someone is something that happens in phases, and it takes a long time — years, really. You first get that “gosh, I think I’m in love” feeling and even commit to the person long before that process is complete. You don’t really know them yet, though. You just see promise in the little bit you know so far. Your mind fills in the rest based on past experiences and other (probably false) truths you think you already understand about love and people.

2. People (including you) want relationships for selfish reasons.

When I was still that starry-eyed young person who was desperate to meet my soulmate and fall in love so we could skip off into the sunset together, I thought I was all about the experience of loving someone and making them happy. In reality, it was more about wanting to be loved, cared for, protected, and made happy myself. I grew up with emotionally unavailable parents who didn’t give me those things, and I saw romantic love as the panacea that would finally fill that void.

And you know what? That’s an incredibly valid, human way to feel, as we’re all looking to be loved, appreciated, and understood a little more. Unless you’re a raging narcissist, it’s unlikely you’re selfish all the time or actively looking to take advantage of someone else. But your reasons for wanting a relationship in the first place are largely about what you think it will bring to your life. You just also assume that your happiness and the other person’s happiness will be one and the same thing.

3. It’s a guarantee that you’ll hurt each other.

Like a lot of people who haven’t always felt loved enough, I’m extremely easily hurt. And once I’m hurt, I stay hurt for a very long time, if not forever. When someone hurts me very badly or does something to betray my trust, I go through a period where I can’t even picture continuing to allow that person to be part of my life anymore. In the past, I often didn’t even bother to try and cut people loose the very first time something like that happened.

I wrongly thought that there is such a thing out there as a person who is so good, decent, and honest they wouldn’t even have it in them to hurt me. No one is that perfect, even a person who is more or less perfect for you. People screw up. They lash out in anger and say awful things they don’t mean. (Sometimes they say awful things they do mean — my personal brand of toxicity.) This will absolutely happen.

But when someone truly matters to you, you find a way to forgive them, and you give them a chance to make it up to you. When you’re the one doing the hurting, you return the favor by holding yourself accountable and making amends.

4. Your heart will be open sometimes and closed other times.

You’re not going to feel madly in love with your partner all the time. In fact, there are going to be times when you probably don’t even like your partner all that much, and they’ll feel the same way about you. Half the time, it’s not even their fault, or yours, either. It’s just something that comes with the territory, but it doesn’t have to be the end of the world.

If life’s taught me anything, it’s that feelings pass — all feelings, good and bad. Just like I have some days when I love my job as a full-time writer and others when I want to throw most of my clients (and my laptop) off a cliff, I have days when I feel like my partner and I are living in a damn Disney movie. Other days, I feel a lot more indifferent, and he can certainly say the same about me. The indifferent times don’t mean we don’t love each other anymore or are no longer suitable for each other. It’s just life doing what life does.

5. It’s impossible to experience love without also experiencing fear.

I hate being afraid. It’s a bad feeling, and not one I feel in very many different contexts, as I’m not scared of very much. But it’s also a feeling I had to get comfortable with if I was serious about having meaningful relationships in my life, as it goes hand in hand with genuine love. Always. And the deeper the love, the higher the risk and the greater the fear. It’s how you process and learn to live with that fear that counts.

Loving someone means opening yourself up to the possibility of being hurt, possibly very badly. It means being afraid of losing them — if not to a breakup, then to death one day — and it may mean being even more afraid of losing yourself. And for extra fun, fear doesn’t always look or feel like fear. Sometimes it’s a dead ringer for irritation, anger, numbness, restlessness, and other things along those lines. It never goes away, either — not really.

But I’ve learned to see fear as a good thing in my relationships. It’s a signal to me that I have something in my life I care about enough to want it around for a long, long time to come.

6. Love is important, but it’s not enough to make a relationship successful.

It’s not even close, actually. Despite what poets, filmmakers, and romance novelists everywhere would have us all believe, love does not conquer all. You can love someone with all your heart and still not be able to love them past major issues like addiction, severe mental illness, or unspeakable trauma. It’s also not possible for one person to love enough to make up for a partner whose heart has grown permanently cold (if it was ever anything else, to begin with.)

Love is an essential part of the recipe for a good relationship, but it’s not the only one. You also need honesty, genuine compatibility, trust, communication, and a wealth of other things. Those are the things that will see you through the really tough times, especially when love seems to be missing in action altogether.

7. Your partner will die one day, so will you, and you have no idea when or how.

Technically, we all know this, but we’re also super good at forgetting that we know it. (That’s probably a good thing because you can’t live your life in a constant state of existential crisis.) Hopefully, you’ll never have to become more aware of this in the worst possible way. I almost did, though.

When we’d been together maybe four or five years, my husband got suddenly, viciously ill with a raging case of pneumonia. He was only in his mid-30s at the time, and he was pretty healthy — certainly no chronic health conditions or reasons to think he might get really sick and die young. But he wound up in a coma in intensive care regardless, and for a while, he wasn’t expected to make it. I spent several days numb and resigned to the idea of being a widow despite only being in my early 30s at the time myself.

Thankfully, he didn’t die, and we’re still happily together. He could have, though, and there would have been no way to predict that possibility and prepare for it. I wouldn’t even have had a chance to say a proper goodbye, but I did learn a valuable lesson. You never know how long you have with someone. Something could happen to them (or to you) next week, tomorrow, or half an hour from now.

Don’t wait to say things that need to be said or make your relationships what you want them to be. I know it feels like you have all the time in the world but you don’t, so treat every day together like it’s your last. One day, it will be, and you have no idea when that day is coming. Pretend it’s today. Your relationship will be better for it.

The idealistic teenager I used to be was wrong about many things when it comes to love. But I was right about good love being worth it. The right relationship teaches you so much about yourself and makes you a better, more understanding person. It gives you someone to face challenges with, go through life with, and grow with as the years go by.

But it won’t be perfect. Realistic expectations are the key to cultivating a relationship that can survive life’s ups and downs, and accepting hard truths is a part of that. Yes, you’ll have to surrender many comforting, pretty illusions people tend to have about love and relationships, but what you’ll ultimately get back in return is so much better and more valuable.