Replying to Girlfriend problems

Hi guys. So as you can tell im having girlfriend problems. We have been girlfriend/boyfriend for exactly 3 years but for the past week she has slowly stopped talking to me and we have slowly stopped hanging out all because of these two fucking douchebags. We were hanging out at the park one day and these queers come up to us and say "why are you hanging out with this loser" so I have a few words for them and beat one of them up and the other runs off. The next day I see on fb these guys add her. So I talk to her and im like "why did you add these guys" and she said "I dont know just felt like it" and ever since she has been talking to them and they have been totally kissing her ass. This has been really hurting my feelings and I dont know what to do anymore. What do I do newschoolers? I really love this girl.