Good evening and thank you so much for your message. I realize it's difficult to reach out. Please know I honor your courage.
My name is ***** ***** I am a psychotherapist in the Metro Boston area.
Oh dear, I can see why you are concerned. I'm a bit confused about something, though....so if they are just friends why does she keep going away and then reappearing in his life? Also, how old are both of you? Have you spoken to him about how this hurts you? What did he say? Do you have any proof that something may be going on between them (more than a friendship)? Do you not want him to have female friends in general or is there something specific about this particular friendship that feels troubling?
My apologies for all the questions. I want to ensure I fully understand your situation.
I look forward to hearing from you.
Completely understood. I do find one of the most difficult parts of this is the way he isn't honoring your feelings. He knows how hurtful this is (and sadly since it's on social media, it's also very public) and I imagine you have asked he discontinue his relationship yet he continues in the behavior.
I would give it one last effort in saying something like this...
"I love the time we spend together and look forward to the weekends when we can. Sometimes the weeks before are really difficult as I miss you tremendous. Sadly, though, what makes it worse is seeing (insert girl's name) comments on social media. She seems to play a large part in your life and it's very hurtful for me. As you know I don't mind you having female friends but the relationship you have with her feels different and I fear it will tear us apart. I want to request, one last time, you discontinue your relationship with her as it is incredibly hurtful to me."
Does this feel comfortable?