You can't come back. If time travel was possible it would be another universe or something. If you changed the past, you'd either go back to a unaltered future, or going to an alternate future where you either don't exist, or there is a seperate version of you already there.

I mean.. The only reason people feel like they could make drastic changes to the past is because we know exactly how it plays out and what to change. We have jo idea how it plays or or what to change in the present to affect the future