What should I do?I'm too much rely on my computer.

No, I don't think that's good for your health. O.o It's not going to be easy cutting the time you spend at your computer down, but if you want to, it can be very beneficial. Try taking up a hobby or finding something else that doesn't involve the computer that interests you. It can be anything that keeps you motivated to try other things and gain new interests. Otherwise, you'll just be willing to sit on the Internet for your whole day, when you could be somewhere else instead trying out other things. It's not going to be easy for you to cut down on the time spent at the computer, but if you really want to, you can make it happen. ^_^ It's all for your own good at the end. Remember that the Internet isn't everything. =D

Definitely 12 hours straight of computer use is not good. It is wise to do other things aside from staying at the computer for that long time. Or should I say you are lucky coz it seems that you have no other things to do like house chores. Also, we should not cut 'real' socialization. Though virtual socialization is not that bad, we should not forget that there is a real world to which we need to keep in touch.

I don't think that it is very beneficial to be on the computer that long. I think you should definitely cut down that time by at least half, if not more. Try to find other things to do: Go running, join a sport, do something a little proactive. I don't know but it just sounds a bit extreme to be on here for 12 hours a day.