Personally, I say don’t forget. This is something you can learn from, even if it didn’t work out the way you wanted. I strongly suspect that you never grieved that old relationship to come to terms with it, and so you rebounded with the first guy who came along. Ask yourself, do you want to be with this guy because you care or because you hate being alone? You say yourself that you’ve been in relationships since you were 16 and now you are 29. But let me ask- when did you ever have a chance to work on your own self instead of worrying about a relationship? You have never been alone in your entire adult lifetime. Perhaps it’s time to focus on you and not worry about being with someone. That is just my opinion.