I just turned 58 and firmly believed I would eventually mellow out as i got older. I was diagnosed with bipolar in 1989. I can't tell you how many times I was convinced I was 'cured". Always came back. During one of my severe mixed moods a friend suggested I might have BPD, as it turns out I don't but during a mixed mood it is confusing. I wish I can tell you it get's better. I guess some times it does. Schizophrenia definitely mellows as you get older, and I have noticed my psychosis has mellowed, but my mood swings and episodes continue. What makes it really difficult for me is I can go months and even a couple of years with absolutely no issues! I feel cured! Only to be rudely reminded no way, not cured. I don't know what the prognosis is for BPD. I can only tell you about myself. I been wrestling with my disorder since i was 6 years old I believe.