The way your treatment has been going on is actually the root cause for your present symptoms and for you not getting well completely inspite of taking the medications honestly. Actually your doctor has placed you on diazepam which is a long acting benzodiazepine which has a strong hypnotic( inducing sleep)action, and you have been taking it in morning , so no wonder you feel sleepy , sluggish and worn out throughout the day. AND to add to the woes he has placed on mirtazapine which though is given in moderate to severe depression but has strong side effects of sleepiness and dizzyness.
So, now you understand why you are feeling the way you feel right now.
So, i strongly suggest that you ask him to put on other antidepressants such as Venlafexine and trazadone combination and stop these two drugs and also add another anti anxiety drug which does not cause much sleep and that is buspirone.
Your doctor should have changed your medications long ago since you were not feeling alright and there was not much improvement in depression either.
So either, he should change your treatment or you should change your doctor.
Wish you get the treatment you deserve.
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