Yes. I do this. I have done this, a lot, through my entire life. And the issue you're describing is becoming a huge problem in my 1-year relationship, and is the main reason why I finally registered for this forum.

I have been seeing therapists for the past 3 years, mainly because I have the luxury to do so (my health insurance thru work pays for such things, for which I am eternally grateful.) Some of my therapists think I sabotage my own happy relationships because there is a history of alcoholism and addiction in my family, to the extent that that I connect love with codependency. The other therapists I've seen think I'm simply not ready for a serious relationship- that I'm too focused on career, friendships, traveling, etc- and so I end up pushing away anyone who gets so close they could interrupt those things. Does any of that sound familiar to you?

Personally, I do think I am affected by all those things that have been suggested to me, but I don't agree with either of those theories 100%.

What I think is happening to me, and may be happening to you, is this: for some reason, I feel that all human relationships end. Inenvitably. I can get along with friends pretty well and have long-term friendships because I don't feel so emotional about friends- I'm not so "aware" of how much it would hurt if I didn't have a certain friend in my life anymore. But with romantic relationships, especially when they start to get really intimate, I freak out and start to push them away because I can't stand the idea of breaking up and also having to deal with detaching that person from my life. It seems to make much more sense to keep that person at a distance than let them get so close that they have the power to hurt me. The only thing that can make me feel comfortable is having my significant other fight tooth and nail for me, and I become immensely sad and disappointed if he doesn't do that.

Ultimately I think it's all about REALLY looking at what you're doing and REALLY seeing what's happening. You don't need a therapist or counselor to do that, but you do have to be ready to be honest with yourself. If you're not ready for a serious relationship, don't get into one and then chastise yourself for not being ready for it. If you're pushing a wonderful man away, question whether you would REALLY be happier with or without him- he may not be that wonderful, or you could realize that you're done pushing him away and you don't want to do it anymore.

Sorry this is so long. Right now I'm pretty much just thinking out loud, because your question brought up so much for me.