one, stuff like LSD, weed, shrooms are so incredibly different from stuff like coke, valium, e's that I don't even know where to start. So I won't. It's well documented, really.
two, if you're gonna do drugs, you have to be prepared to lose friends. people WILL look down on you for it, even if you only did them on a single occasion. it's just a fact of life. some people are closed minded like that. **** them, you don't need them.
three, contrary to what I just said...you do actually have a problem. you seem to be sitting on the fence on accepting you have a problem here. stop trying to rationalise your bad decisions and cut back. drugs are okay, drug addiction is not.
four, I typed that pretty much off the top of my head and I'm incredibly tired, apologies if it's not particularly articulate or well structured
EDIT: also, I'm not sure if you're the kind of person who should be taking drugs. the kind of person who should take drugs is confident, secure, and basically just doing it for a laugh. you sound to me like the polar opposite of that. basically, incredibly at risk of addiction.