If your thyroid is 'sluggish', this could be the cause/worsen your depression and weight gain issues.
I have a question for you, have you ever been screened for bi-polar? Sometimes you will be having these mood swings and lashing out episodes because you are bi-polar. There are different types of bi-polar. You might talk to your shrink about it. Shrinks make mistakes too, they go off what we tell them alot. If your most prominant symptoms are not being told to your shrink they may misdiagnose your depression. You could have a bi-polar disease. Anger and mood swings are not just depression only symptoms. Also I have taken alot of depression meds and yes they cause weight gain. I understand, cause I gained like 40pounds in two years from meds. I took , paxil, zoloft,prozac, lithium, depakote, they all cause weight gain. Especially if you are changing around your meds, also you will go through horrible mood swings when you are changing meds. Your shrink should have told you that. A friend of mine would just check herself into the hospital in the psych ward when she had to change her meds so she wouldnt take out so much on her kids and husband. My friend is also a registered nurse. She said that there was like three other nurses in with her. They were changing meds too. So don't feel alone, med changes are hell. talk to your shrink and good luck.