do I choose the wrong friends?

[lhc1575]

Here's the most recent situation:

 

 

 

Basically, someone I considered to be a good friend hit on a guy that she knew I really cared about and had had feelings for all semester (we're all in college). It put me in a bad situation of determining what I can and can't put up with. I would never do anything like that to a friend, and her excuse was that it's just her personality--but unless you walk around unconscious, you are aware of what you do. She was a toxic friend for a lot of other reasons, being clingy, controlling and judgmental of other people, but after this last situation with the guy I couldn't put up with anymore. I tried to see things from her perspective and understand her insecurities...but in the end, it was more work than should be needed in a friendship, and it was all on my end. She never accepted that her behavior was wrong and that it was the reason why her ex-friends cut her off in the past. No sense of self-awareness.

 

We hashed it out and she turned on her ego and acted like an insecure guy who knows he's about to be dumped, but turns it around so he's the one doing the dumping. She could tell I've been putting distance between myself and her, and she put the blame on me for the situation, unable to understand that her actions pushed me to it. I wanted to try and work it out, but she decided to ditch me as a friend. Now, she has no one.

 

I've had problems with friends in the past. I have a good amount of friends, but only a couple that I'm really, really close to and can confide in and depend on. I'm definitely an introvert, I enjoy my space but still am there when people need someone to talk to. The friends I've had issues with seem to have the same traits: More outgoing than me, aggressive, emotionally damaged/insecure in some way that manifests into negative behavior, clingy and needy. These people also want to get close to me fast, and I think it's because I tend to want to fix people rather than see red flags as warning signs. I want to be there for them...but am I making a mistake in trying to do this? Is this why I've had issues with friends? Do I keep making the same mistakes?