Work Drinks, Always Interesting

Last night, work organised drinks for the staff to farewell a staff member who was leaving. These functions usually include the same group of people - or the same kinds of people. A select number of management and usually anyone who works directly with those managers. 
I usually go, but I'm not really partial to going out and having drinks with people from work. The reason is because it goes against my idea of what a work environment is, or should be. I understanding getting to know the people you work with, but casual drinks and dinner is usually reserved for my friends and family and being realistic, these people will almost never be anything but workmates. So it sort of crosses my personal space barrier. It's inviting them into your personal time, or the life you have outside of work. I think because I don't find it genuine. People are there for the free drinks and food, and in the case of last night, it was more of a be-a-team-player kind of thing. 
Anyways, last night was interesting. One of the upsides is that once everyone gets a few drinks into them, they start talking. About all the things they probably shouldn't talk about. Always fun.
We start talking about the company - naturally (what else do you have in common, really?). And we talk about management and the structure, the future of the company and our futures. We touch on the politics around certain staff members and management. As you do.
Anways, we start talking about one person in particular. And it seems this person is quite known for being somewhat, manipulative. What you would call, covert aggression, the smiling assassin. Usually a great person to be around, and most people would say they are great to work with. But they're clever, and they know how to use people to their advantage. 
Now, I have to admit, this person has gotten me. A couple of times. I felt stupid, because I tend to read people quite well. I think I missed this one because, in the past I've known people who's tactics are to be covert aggressive rather than someone who's personality is covert aggressive. The first type, are without a doubt easy to spot. They're pretty genuine and then you see the red flags when they're being manipulative. They are usually nice people and they know when to switch back and forth. Calling them on the behaviour means you've won the game. You've pulled the cover off and they've been seen. 
This person, this is they're personality. They are never, ever genuine. They are always playing. So, if you'd dopey like me, the laid back, kind, supportive nature is taken as just that. But no. It's all part of the game. The thing is, with people like this, you can never be sure. You feel that you've just been screwed, but can't quite put your finger on why. You've got no proof.
So anyways, someone admits, that they see this person doing it. And they saw it happen to me, and although I admit I was aware, there's this realisation or confirmation as you will. 
So at the moment, having a good hard think on how I can get out of the game. I don't want to play it with them - they'll win for sure. They were born into it. They've had a lot of practice. So I want to figure out how to not be a part of it. 
As always, my life is subtly complicated. Fun.