How it's going with the new roommate? You said he is going to move in soon.

I often have these sudden moments of desperation just from having a thought of a possibility I don't want to happen, but also often the reality is better than these dark expectations of it...Though in that moment I'm too lost in the dark emotions to be able to not get desperate even though I might know rationally that it won't last forever.

Also you mentioned you got some medication, but no therapy. I think therapy would be very helpful though... I've been told that medication doesn't really help with BPD, but maybe it depends on the symptoms, everyone is different.