I also take an antidepressant. While it does make achiving an orgasm a little harder it is not impossible. My doctor suggested that I stop taking my meds on the day I plan on being intimate. I still take it, I just wait until we are done. My doctor said that the reason this works is because antidepression medication works only when you take it. It is not time released like other meds are.
It is possible to try some meds, e.g. at www.you-cheap-drugstore.com