Remember... we're a sensitive species. Lol, you know what I mean.
Every facial gesture, word, movement, action and intention is skillfully analyzed, judged and reported to the general consciousness... as something a little more distorted than reality. You expect to be conspired against and victimized... and then you see it.

It's entirely possible you have less than friendly relationships at work.. but not ALL of them. You need to try and engage your logic against these notions. How likely is it that EVERYONE is trying to get you fired? Or even half the people in your work?
It's so unlikely you have you make yourself feel it. Like... this just doesn't make sense. Then really consider some things...
Why am I feeling this so strongly?
Am I paranoid about their opinions of me? Am I insecure about my work performance? Am I insecure about interactions with them? Do I think I'm not great enough, what they want, for them to like me at all?

You're never, 'just being mental'
And like using logic, we have to combat the black and white thinking. They do not either want to get rid or you, or you are 'mental'
It's very likely, through stresses in life, and especially work, you're going deeper into your BPD and letting it have free reign over your thought processes and conclusions.

You need to step back, analyze logically and go from there. Do you need to address this in depth in therapy? Do you need some medication to help you feel happier and stable and able to look past these issues?

Hope you're okay though, robbstar