Being a Veteran in your boat with the SSRI’s I can tell you this much. Work with Doc and get them stopped as well as work to get the label removed. Those events will always haunt us, but that label can keep you from your dreams. Trust me. At 46 and Retired Military I am no longer concerned about flying for the airlines so I’m not really working to get there. But being here and helping out where I can and offer assistance is what I do. I’m not a lawyer and not a Doctor, however. Seek those Professionals for Advise. I have called a couple of AME’s in the past about this kind of thing. Contact the ones you are going to to find out exactly what their going to do about it before going any further.
Also kind of depends one what and where you want to go with your flying. Certificates only require a Third Class up to MEI. However to work at the airline level or Commercial level they may too require a 1st Class. But to get your Certs you will only need a Third.
ATP likes you to have your 1st Class due to the ultimate goal of ATP grads is upper level Professional Flying which in turn all require a 1st Class.
NOW with all that said, if your goal is to fly, then go fly. By all means go fulfill your dreams and fly, just have realistic expectations on the possible outcome of the medicals. 3rd Class is in reach as well as a Sport Certificate but it’ll be a “fight” or rather it’ll require some effort and work to get the 1st Class after having PTSD and taking SSRI’s.
GOOD LUCK BROTHER, I wish you well and safe flights.