Should I seek therapy?

About 11 months ago I fought with my girlfriend at the time and told her she gave bad oral sex and called her another mean name. The fight was about so many things.

I tried apologizing but she rubbed it in my face how she is sleeping with this guy. The guy I was so suspicious about to begin with. And it sucked cause I had to block a female friend yet she would snap him all the time.

Anyways 11 month later she is still with him while everyday I kick myself

I was 18 when the relation ended and she was in her early to mid 20's
Should I seek therapy?
Add Opinion