I really need help......?

I've wanted to kill myself for years now, but have always thought about the heartache it will cause my family and the consequences after are just running through my head evrytime I want to do it and it ends up preventing me from going ahead with it and I bottle out. I don't want to leave behind anything bad, I just want to die and thats it, but it's not that simple. So, what do you recommend to someone who constantly wants to die but is far too scared to kill himself? and do you think it is an act of selfishness because I think if you want to die then it shud be your choice.