I take Trazadone which is actually an antidepressant and used for insomnia and it helps me sleep I haven't had any problems sleeping with it.
I am on Sub too, and don't really have a problem sleeping, but the doctor also gave me clonodine, which I take alittle of almost every nite. But if you are spliting your sub dose and takeing in the AM and again later, you may be takeing it to late. The Sub can cause alittle sleeplessness if taken to late in the day.
Please don't take this wrong, but could menopause be an issue? Because that will definately cause sleep problems.
Take care,
Magi