I have a pretty strong natural filter. Years of therapy and three different therapists have yet to get me to a place where I can truly open up, even when writing on a page I know no-one else will see.
Two days ago I did weed for the first time. I accidentally took a much larger hit than I meant to. For the first 15 minutes I had a complete out-of-body experience; nothing seemed real, I felt like I was floating through space, able to peer into reality at will, still not quite trusting that it wasn't all a dream. I'm pretty sure the term of art for what I experienced would be a psychotic episode.
After that... I lost my filter. Like, it was gone. And my mouth was a conveyor belt connected to the emotional part of my brain. No logic, just uninhibited speech, for 45 minutes, all while sobbing harder than I have in my entire life.
I exposed every last deep, dark secret I possessed. My fear of never being good enough. My fear that everyone in my life will leave me at some point. My fear that I've done so many hurtful things over my life that I'm unworthy of love and of the friends I have. And many more things I won't be sharing with the world, at least not yet.
Inside, it felt like my brain and my mouth were connected by a pipe, and all I could do was sit back and watch in horror as the very depths of my mind were laid bare for all to see.
A good friend of mine was with me while I did it. She heard everything. It's a mark of our friendship that she held me, reassured me that she loved me for who I am, not who I want people to think I am. Our friendship is even stronger now, something I would never have thought possible before having that experience.
It was terrifying, and yet oddly theraputic. I'm seriously considering cannabis-assisted psychotherapy now.
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I guess what I'm trying to say is: there are a number of substances that induce mind-altering states in ways that are relatively safe and free from long term effects. If you're someone who can't seem to open up naturally, don't be afraid to try them. They just might change your life.
(As with everything, consume appropriately and safely. Have someone experienced in the substance you're consuming keep an eye on you. And for god's sake, don't do anything known to be addictive or to have severe negative side effects.)
Also, find friends who you can truly be yourself around, who love you even when they know the absolute worst about you. It makes all the difference to know that someone loves you not for who you want the world to think you are but for who you actually are.