<human>: i think i might be borderline insane. I fucked around with some drugs, and ever since my perception on the world has changed so much, to the point where all my mind is doing is pondering life, and meaning. i go through my day normally, do my schoolwork, enjoy spending time with my friends, love my girlfriend, but i feel like it's all just a front sometimes; like everything around me is just a projection of what my mind wants, like i'm the only person truly alive, and everything else is just made up.

i have way too many thought processes that have lead to this conclusion for me to even try to recount any of them, and it all began with the drug experimentation last spring.

the only thing that lets me think i'm sane is that a crazy person wouldn't know they were crazy, so for me to think i'm crazy i can't really be crazy. crazy, right?

Can you summarize the given text in a few sentences?
<bot>: i feel lonely sometimes, even when im with a group of friends having a great time, because i think it all might be my imagination and everything is fake.