Your situation reminds me of mine some time ago. I see the cycling and really a mood stabilizer may help. Are you keepnig tracks of your mood high and lows? Docs don't always are so careful to remember exactly. I prepared a chart for pdoc, and he actually sorted out the good med! I really think pills can do something for you.
My suggestion is DON'T talk about suicide to anyone who can't understand. Not your parents and not your friends. But DO talk about it with any doc and psych you deal with (and try to deal with some ASAP).

Good luck!