I was taking Seroquel for several years. It always stuffed up my nose at night about 1/2 hour after taking it. It did seem to help with sleep and in stopping the night awakenings and nightmares. Unfortunately after time I developed restless legs syndrome from this medication. Did some online research and discovered the link between the two (I didn't know what was going on). I am now on Mirtazapine and Trazadone for sleep and depression. The mix seems to be a good one for me, I feel as though I'm having a "natural" sleep. And no hang-over effect in the morning. I was just started on Olanzapine though, because of ongoing panic attacks. Another atypical antipsychotic but, like Seroquel, given at a very low dose (5mg).
Hugs to you, I hope something will work for you that doesn't cause so many problems.