My dad is bi-polar or maybe has schizophrenia (will probally never find out since he refuses to go near hospitals) and had some bad experiences with weed. Although he was doing acid as well. He was put into a mental institution for months and when he was let out he quit the acid. He started smoking weed again but said that it caused effects similiar to acid and that he was starting to trip out while sober. Although he has now recognized that he is probally bi-polar and was probally having sypmtoms of psycosis. He also went to jail and juvey for weed. Oh and he got taken away from his mom. SO some people may have traumatizing experiences with weed.