<human>: Condense the text into a few key points

I'm seeing red over this situation and fear my next reaction to it will be emotional.  

I've been seeing my girlfriend for about 5 months now.

One of her best male friends has many connections to me and she has been excited to finally introduce us.  When I did, he was incredibly rude and constantly saying things to make me feel intimidated.  I was shocked considering we had many things in common that I am sure he'd heard of.  Aside from that, he was incredibly rude in general, constantly implying his wealth and how great he is.  I am used to people like this, but I was shocked at how her friend group laughed at these jokes and seemed comfortable around that behavior that I do not typically accept.

I circled back with the other mutual friends I have with him and they all confirmed that he is a terrible person.   

This is making me insecure in a number of ways.

* to a lesser extent, it's making me question my girlfriends judgement and tastes

* to a greater extent, I am offended by this guy and I'm going to have to deal with him again and again.  He is unphased by being a jerk to me, to a very extreme level, and it's really getting to me.  

* He's likely into my girlfriend, which I obviously don't blame him for, but it makes me uncomfortable.  He was bragging about her enjoying his wealthy families houses in the past, invited her on a trip [work related] in front of me, and touched her arm within minutes of meeting me. 

I was really taken aback by this behavior, and my girlfriends lack of empathy towards the fact that this guy was trying to "alpha dog" me, or at least clearly make me uncomfortable.
<bot>: I have a problem with her male friend, it's making me insecure and I don't know how to address it.