I'm a highly sensitive person and at times my feelings can be very intense. One thing that I find with BP is my mood often doesn't match with what's going on in my life. For instance great things can happen and if I'm depressed it won't bring me any joy. When I'm too high and in a "happy high" everything seems great even if my situation is less than ideal.

From what I've read borderline personality disorder moods tend to be more reactive to what's going on around them.