i just get overwhelmed, much like jadedbutterfly described. I am good for a while, then I just can't make it in anymore. I think my depression and ptsd play more into it, but if you take the bpd into account, I guess the self-harming and suicidal thinking make it hard to show up. I end up quitting before I'm fired most of the time though.
I'm decent with socializing, but only with a select few people. I rarely make lasting friends at a workplace, and even those I tend to screw up eventually. I just don't feel like I'm worth much, so I don't push to hang out with people.