Can a major rejection affect you even years later?

About 6 years ago (then 22 years old), I got rejected by my then long-term HS sweetheart. We had known each other since we were 16 year-olds. I wanted to move things forward. She didn't. Her answer was no.

For the longest, I had a hard time expressing more emotions to women. I started having several short-lived casual relationships. I would tell the woman that it's not serious. It's only been recently that I've been going out on several dates with a woman I find something unique in. I'm just taking my time though. I still get that horrible flashback from that major rejection.

Can a major (huge) rejection affect you even years later?

Can a major rejection affect you even years later?
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