I agree that the gig thing is something you focus your fears and negative inklings about the relationship upon (if the gigs were gone I think you would find something else to focus on).

But the gigs I think ARE still a problem. They DO put your relationship on hold. He IS having and seeking inappropriate relationships. You have every reason to feel you are being direspected. You have been made unwelcome. You have every reason to feel threatened. He IS going beyond the boundaries that were agreed upon.

Not just are you feeling forgotten, not only are you feeling frustrated, but a big part of your feeling threatened is that you are being excluded from all aspects of these activities - especially the social.

I think this might be the way to approach working on this. Finding a way to be involved - especially the social aspect. How do you feel about insisting you tag along to those social activities that happen outside of the gigs themselves? How comfortable do you feel just showing up? This might be a way to signal to your BF that you are interested and perhaps willing to accomodate his passion. Are there otherways yu might be able to participate?