Sometimes meds poop out on us. They work great... until they don't. It sucks. Sounds like that's what happened to you if it worked before.

It's ok to try a different SSRI because it may work for you, but there are also SNRIs and Maos etc..

I know in my case that Abilify didn't work for me (aripiprazole), but rexulti (brexipriprazole) works wonders even though they're so similar, so you never know!