I think the important aspects of a relationship, especially the things that decide whether or not it fails, becomes visible very early on.

I met someone, and I was swept up in the romance. Turns out she is very defensive, and gets angry easily. She would be hurt if I criticize it too much, and I feel we will both be hurt if I don't talk about it enough to learn to deal with it. I don't want to fail again, I'm amazed she hasn't just run away with how ugly I am.

My own issues that ruin relationships, depression, self-esteem, self-hate will be hard to deal with when she gets angry. The two problems could excite one another, and we'd burn out. I don't want to lose this, not at all. I believe she's a beautiful person.