How do people stay in love for that long

This is more of a question for people who have been in long term relationships, but how do yall not get tired of them? Ik partners take breaks from each other sometimes, but I genuinely can’t see myself liking someone enough to be with them for over a year. It’s not that I’ve never had a crush before, but anyone I liked became boring and I usually ended up disliking them once I got over my crush (they weren’t assholes I just didn’t like them) does your love for your partner stay the same over time or do you see them as more of a friend in a non-romantic sense?