Well you have definately hit on most of the symptoms of depression so if you want to convince T you are depressed, do as Shezbut says and print out this post and bring it to your next session with T. I think the only one you missed was weight loss. you could google Becks Depression Inventory and take that and bring it in to her as well. It is an inventory counselors adminster to clients to gauge their level of depression.

Anyway, advocate for yourself and let your T know how you really feel. Good luck.