I don't mean only having psychosomatic symptoms, but actually falling sick or having a preexisting illness get worse. 

I've noticed a connection between my BPD flare-ups and common illnesses. I rarely get sick, but when I do, it's almost always when I'm mentally in a crisis. It also seems to take me longer to recover when that's the case.

Has anyone else experienced this? I know stress can affect the immune system, but does it happen to this extent? Or is it just a coincidence?