I posted here not too long ago and the answers I received really helped me shed some light on my boyfriend's behavior. I'm back for more and I hope it's okay. 

My long time boyfriend is a jerk to people close to him and it's like he prefer running away from his responsibilities rather than doing the right thing. I'm looking for a BPD connection, if there is one. 

Here goes:

A year ago, after dreaming about it for a very long time, he asked his best friend if he wanted to start a business with him and his best friend said yes.

Seeing as my boyfriend's credit wasn't the best, his best friend signed the lease and bought the first project they were going to work on. It cost him close to $8,000 with a 6 months lease on a work space. 

A week before the big day, my boyfriend changed his mind. Saying that he wasn't sure about it anymore and finding a lot of excuses not to go. The space was too small, too far, not enough light. A lot of complaining about his best friend too. All of the sudden, his best friend became the worst person in his life. Someone he's known for almost 20 years. From calling him his brother to insulting him and the friendship they have.

It's not what he wanted to do anymore in his life. He wanted to work on something else instead. A lot of unnecessary drama coming from my boyfriend. 

Like he was trying to sabotage his own dream by getting cold feet. He abandoned his best friend with everything. The project, the space and the debt. His best friend is now thousands of dollars under because of my boyfriend. 

Seeing as I didn't agree with him hurting and ditching his best friend like that, we sat and discussed things. I wanted to understand what was going on in his head at the time for him to do that. From dream to reality to him running away like that. He didn't know, couldn't give me a clear answer. Just weird excuses that didn't make sense indicating he was scared of taking the plunge. 
I told him it was very wrong to do what he had done to someone like his best friend, and I asked him to fix things and man up to his words. 
He promised me that he would. 

3 months later, nothing has been done. The drama with his best friend is giving him a lot of stress in his life, and he keep getting mad at his best friend for being mad at him. Not understanding that his own actions are what's causing this whole mess. 

Tonight, I put my foot down and I told him to go and talk to his best friend in order to find a solution and start working on something he's been wanting for a long time. 
He refused. Same thing. Harsh and mean words towards his best friend. Saying things like he never wanted it. Not true. Just being a jerk. 

I'm wondering if his actions are linked to BPD. Getting cold feet like that about many big things in his life. Other situations happened where he ran away too instead of facing the music. 