Welcome to PC. I'm sorry you've been hurt by lost relationships ((I'mNotReal)). I know the feeling of not wanting to risk being hurt again. Are you in therapy because you could bounce your feelings off the therapist rather than blurting out your feelings prematurely to your partner.

You can also look up 'fighting fairly' websites and you both could use those techniques to communicate better. Thinking before you talk and ask yourself the question first helps, as well as wondering if this will matter in 10 yrs. You can also look at the patterns you follow and learn from those mistakes. We all experience pain in relationships at some time in our lives. I hope it gets better for you.