One of my best friends (play sister, daughter) recently committed suicide by shooting herself in the head.  She lived with my family and I for over 20 years (came when she completed rehab). Her drug of choice was cocaine.  She had been free for over 20 years (or so I thought).  I helped her buy her home, furnature and car.  I have always been there for her during hard times.  Her mother was diagnosed as being bipolar and my friend often had "bouts" of depression (wanting to be left alone)...be we all have this.  After the suicide I realized that she was back using drugs....other friends of hers knew but did not tell me....She told them not to tell me.... I think our relationship went from friendship to sistership to me being more of a mother figure.  I instilled tought love and would not give her money if she was overdue on a bill unless she worked out a way to pay me back.  I always told her if she got into a jam to let me know.  We were 9 years apart in age she being younger than I.  She refinance her home, then sold it and was being evicted when she committed suicide.  She and I spoke at least 5 if not 6 times a day, but had not seen her in 3 weeks (prior to her suicide).  I am feeling so guilty that I did not know  sooner that she was using again;  that she did not want me to know , and why she did not come to me for help.