Sorry to hear you are feeling depressed, the same thing happened to me a few months after i finished treatment, i would cry at the drop of a hat, my local doctor prescrdibed anti depressant, and leaving his office in tears i told him i didnt need them i was a strong person, and what did i have to feel depressed about, i had coped with the treatment of breast cancer. A couple of weeks later with the prescription still in my drawer i had an appointment with my specialist and the minute i sat in his chair and he asked how i was, i started bawling.. he explained that a high percentage of women who have gone through breast cancer suffer from depression, and that i should take the anti depressants for a year,, i still insisted i was strong and didnt need them, we discussed it a bit more and he suggested if i didnt take these i could go further down and treatment would be harder.. So i gave in and took the pills, i must say it was the best thing i done, i took them for a year and i then knew i was back to normal and he suggested i cut the dose down for a couple of weeks then stop them, which i done and have felt great since, that was 3 year ago, so i think what we done realise is, that we have been too busy concetrating on getting through the treatment and when things start to return to normal it hits us.
i hope this helps, as i say i am not a person who takes medication lightly, but in this instance best thing i done. so maybe discuss this with your doctor.