The mini-pill is pretty crap as far as birth control for most people (always use backup methods), but it tends to be excellent at regulating hormones to a certain level.
Will that level be life changing, barely noticeable, or make things infinitely worse? Only taking it for a time will tell.
In my very limited understanding there is a tendency for
- People with menses linked depression to develop PostPartumDepression
- People with menses linked shazaam (increased sex drive, creativity, etc.) to develop AntePartumDepression.
Which means that the probability is that it will help lift/negate your depression... As the way birth control pills function is to trick your body into thinking you're already pregnant. Downside... Is that going off the pills can trigger PPD like symptoms, the same way as the preparing-for-pregnancy hormones getting cut off when you have your period are causing a sudden sharp mood change. Which is good to know ahead of time, so you can plan for it.
Hormones are wacky. I had a girlfriend for years and years who was (still is) severely bipolar. First time she got pregnant? Her world became normal for the first time since puberty. Off meds. She tried hormone replacement to very limited success, and decided to become a surrogate, instead. Her body & brain just looooove being pregnant (love her to pieces, the bitch, mine hate hate hates being pregnant :P). It resets everything just right for her. So she had a baby every 12-18 months (give or take) for 25 years.