I have been on antidepressants for 20-something years. I took SSRIs for a long time, but for the past several years I have taken Effexor, a SNRI (just a different class of antidepressant) which works very well for me. I did, however, have to have my dose adjusted for whatever reason after I quit.
The same medications may act very differetly with different people. If you are not happy with the one you are currently taking, talk to your doctor about trying a different one. You may also find that since you aren't drinking, weight gain may be a non-issue this time around.