I find insomnia the worst symptom of my BP condition, so I had to chime in. Ambien was only giving me 4 hours of sleep for about two nights at my peak hypomanic phase. I have learned to avoid strong coffee and sweets during insomniac. I go swimming, and I take either antihistamine (Hydroxyzine up to 150mg), but I have never gone above 100 mg or 25-50mg Thorazine.
Now if I do not sleep one night, I will sleep the next day — no big deal. You must not get anxiety over insomnia because that is the vicious circle. I wish you the best to find a solution. When you refuse to get up at night and force yourself to remain in bed, then you start "micro dreaming", and if you do not stimulate yourself, eventually you fall asleep. I get rested this way when hypomanic. Lithium allows me that rapid change of thoughts, agitation, and panic are in abeyance.

Oh yeah, the other night I was insomniac, and I took THC and CBD if nothing the anxiety went away and I listened to music all night!