Afterlife or what?

I have been afraid of death for some time. I am thinking, what if afterlife does not exist. I am a Muslim, and I choose to believe in God and afterlife etc. However, there are many logical points that make religions look like they are created by men for their own interests.

Apart from trying to make the world a better place, the religions try to instill fear and thus some responsibility in a man by the fear of hell. There is also the rewarding afterlife for those that are good to other people in general.

It is very much like the caste system in India. Rich people do not want poor to disturb their lives and just be happy where they are, so they say "if you were a good servant, next time you will be the king".

The western religions and Islam say "work like a dog all your life, and be good to everyone. don't worry you'll have all the eternity to rest and have fun!". So people try to be responsible and work all throughout their youth, during which they could have done the funniest things, until they can work no more without being a hassle to their employers at the ages of 60-65 when they cost more than the amount they help their employers earn.

So basically, the religions are trying to make rich people richer, by promising a fun and eternal afterlife.

But what if there is no afterlife? What happens? We will have wasted all our lives working to make our rich bosses richer, and maybe we have done some good for the rest of the people that have no effect (or actually add no benefit) to our lives.

I think it was Adam Smith that basically said, if everyone was selfish, world would be a better place, in a nutshell. So I work my ass off for people and when I don't get what I deserve during this life, I become angry and start hurting people (doesn't have to be physically) and become more detrimental to society overall. So if I were selfish and tried to make only myself happier, I would be more beneficial to the society overall. And if I am selfish, I will not regret my life when my time comes to die and I find out there is no afterlife. Actually I can never be conscious after dying if there is no after life, so I would not be able to regret either. I mean looking from today I would regret living not for myself and my happiness but just to be able to live -that is, to earn money-.