I also get this on occasion, it's like all of a sudden a fog has lifted and I become super excited about everything and I want to do everything and I believe I can. It brings along thoughts of "I'm all better", productivity, hyperness and like yous said confidence. I used to get this a lot when I was going out every weekend a few months back.

I would go around and be all cocky, confident and feel on top of the world. Even when I was staying in and drinking, and I would hit a high and life was wonderful. Like yous said, the dreaded comedown must be avoided so I used to end up frantically avoid this but it never worked for long.

When I look to these sort of periods, it almost feels delusional. Like a false sense of self? But I'm sure as yous know, people that have borderline experience moods differently, in the sense that they become all consuming and single-fixed. Therefore, although you logically know there is going to be a downfall, at that time the delusional thoughts of being ALL better, and EVERYTHING is amazing is attributed to that consuming happiness. Just like a depressive mood would conjure up thoughts of, it will NEVER get better. I CAN NEVER do these things.

Gotta love black and white thinking... >.>;'