Ah. As someone who went through the same thing (minus the ptsd), next time you get in a bad mental spot go see a psychiatrist and tell them about the bipolar diagnosis. There are some very mild mood stabilizers out there nowadays that don't zombify you. (SSRI's can trigger manic episodes and cycling in people with bipolar, fyi).

Also just making sure you don't trying and deliberately alter your moods with caffeine, weed, or amphetamines will keep you relatively stable (even without drugs). Although if you start having a full blown episode it's worth keeping what I said above in mind.

Sorry if the advice is unwelcome. This is just what I found helpful.

People with bipolar often use caffeine, weed, or even amphetamines to deliberately trigger hypomania. Feels good, but unfortunately it also increases the frequency of depressed episodes. It's like Karma.