I am 18.
I don't know why but I feel like I am competing with my ex-girlfriend (lets call her X) who dumped me around 2 years ago. It was the first relationship for both of us and I was very emotionally attached to her. Since we broke up I hit a slump in my life and entered a depression phase for 6 months or so. I then felt I had moved on, and decided to start dating again. After that I went on to date 3 people. I never felt the same spark and always thought the relationship wouldn't work out. I ended all three of those relationships.
I have now finally met a girl I like (lets call her Y). I took it slow this time and really got to know her before getting into a relationship.
Now about the competition bit: X got into an Ivy League College.
For some reason I feel insecure about this and correlate it with me holding her back. To somehow prove her (more like my own assumption) wrong, I have started studying very hard and trying to achieve as much as I can. I do enjoy the productivity. But I hate the motive. I want to discuss this with Y and try to overcome this insecurity.
However, the 3 girls I dated in between all pointed out that it was very irritating when I spoke about X. It also hurt them in many ways and destroyed the chance of the relationships working. I do not want this to happen with Y. I do not want her to think I am not over X and yet be able to discuss my past.
How do I open a discussion about this topic without making my current girlfriend insecure about our relationship?