What happens when quitting?

I have been on Lexapro for a year and a half. My current dose is 20mg a day. I have never been able to sleep while taking it. I sleep an hour or two and am wide awake. Since I can’t sleep I take trazadone every night. I feel tired all day long and I don’t want to deal with that anymore. I have zero ambition.

What happens if I stop cold turkey ? How long until I feel like myself again?