Hey friend, ecstasy is a very harmful drug when you do it on a regular basis. If you can limit the use of it to only every now and then (say 4 times a year or so) it's not exactly good for you but I can think of a lot of worse things one could be doing. The long-term affects of ecstasy use aren't really known but I can assure you that it isn't a positive thing. Especially because when people do it often, it can cause serious problems. I used to do ecstasy but I quit after I realized it was the cause of my depression. It really screws with your serotonin levels and pretty much drains them. It comes to a point where you just won't feel happy after you take the drug for a while. It sounds like your friend may need your help. It may seem like a bad thing to do, but you may want to consider talking to his family and other friends about the problem and seek help. You could be risking your friendship with him/her but in the long run, you'll be playing the part of a true friend because you care. I have a lot of experience when it comes to drugs and if it wasn't for my friends and family stepping in God only knows where I'd be. I wish you the best of luck.