3 in a couple - me and her friend(s)

I've been with my girl for a year now. We've had our ups and downs but I believe truly love each other and we've had some amazing times together.

When we first got together she joked about meeting her best friend for the 'approval test'. 'Not many pass' Haha etc. I have no idea if this has any relevance but he's a gay guy. No problem. Like this girl therefore want her friends to like me. Deep breath. Drinks, fun, best behaviour - all good. Ask her how it went. 'Good'.Think I passed the test and thought I had been accepted by her tight knit group of friends...until months later.

She comes to me saying he thought I didn't like him. Nothing of the sort I said. Actually really liked the guy but alarm bells started ringing. Had I done something wrong? No...apart from be myself. Sometimes that's enough with me. I can be abrasive without realising. But there was no trigger event I'm aware of. Not long before this my girl and I had had a rough patch, took some time out but sorted our mess out and got back even stronger. This happens. Was that it? I'm guessing the guy had a change of heart and just taken a dislike to me or just never liked me in the first place. I start to tear apart everything I may have done - that bad joke, that time he jested about me flirting with his boyfriend etc. Can't pin it down. But the fact was that she was now concerned that I was not getting along with her long time best friend and all of a sudden I feel like I'm a troublemaker in their little tribe. I kinda felt we were in the rudiments of trouble. This guy had seen many a BF come and go and I can feel the daggers now coming from him on subsequent meetings. I can't tell my girl cause she'll feel like I'm causing trouble and I'm scared me voicing my concerns would just fuel his assertion I didn't like him. So i keep it all to myself but it's taking its toll.

Things deteriorated. My girl and I had been out all day drinking far too much wine on a sunny summers day a few weeks ago. I'm not the drinker they are anymore and certainly haven't got the capacity and control they have when I try to keep up. He turns up and in that state and after all the increasing tension I must have pushed his buttons and upset the guy. Hands up. My fault. The strain had got to me and that's how it came out.

Bigger trouble. Her birthday 2 weeks later. He verbally full on assaults me unprovoked in public I walk out. I clear the air with my girlfriend later that night but the damage is pretty much done. All her other friends are all too aware now. So here I am. Hanging by a thread and punch drunk. Advice pleeeeease! Too complex for my male head.