What do you do when you've been feeling ok?(for lack of a better word, not good not bad, nothing really but not empty) for an extended period of time?

I know I should be grateful, but the typical BPD feelings of perhaps I 'made it all up' or was 'never ill' creep up every now and then. I know many of you feel the same way, but I've identified with feeling such misery and anguish, that without it I feel sort of lost and fake. It's as if I'm craving the drama and attention my bad days might bring me. 

It's a constant battle between feeling such highs and lows, and then feeling nothing, always craving the other.