Did you ever get an ultrasound of your thyroid? Your T4 and T3 levels? See your GYN or get a new endocrinologist.
Postpartum Thyroiditis usually resolves by itself a few years but in some cases it can permanently damage the thyroid.
http://www.endocrine.niddk.nih.gov/pubs/pregnancy/
I agree with Fufu, if you're not clinically depressed those pills may only add to your problems with their own side effects like - drowsiness, insomnia, dizziness and headaches. **Never stop taking antidepressants suddenly though, you must be weaned off slowly or you'll go through physical withdrawal. Not a fun experience, it could land you in the hospital.