If you are a Christian, do you really really believe in Heaven?
You know whether you believe in Jesus or not, so you know whether you are going to Heaven or not, right? Because Jesus is so merciful, that if someone believes in Jesus, he goes to Heaven, according to your religion. So, if you know that you are going to Heaven, how can you wait?
Personally I am bad at waiting. For example, if I would going to receive the product I wanted so bad in a week, I just can't stop thinking about it. If there is a way to get the product faster, I would do it. If I were a Christian, and if I knew that I am going to Heaven when I die, probably I can't wait to die. So, suicide is a sin (which book in the Bible says so?). Yeah, I am not going to suicide because then I cannot go to Heaven. But I would participate in every chance I could legitimately die. For example, I would join the army or firefighters. I would try to rescue every people I see on the street or on a subway railroad. Even though I would not suicide, I wouldn't care about taking medicines or exercising. I would eat lots of junk foods (no Bible passage says thou shalt not eat hamburgers, does it?).
Atheists don't do those. Because they know that their lives is once and the most important thing to them. Of course some of them would sacrifice their lives but only for very big big reasons. They cherish their lives. So which one is good for humanity?
According to what you say, if you go to Heaven, you will have eternal life, and you will meet all the people you loved but died, and most importantly, you can meet Jesus. Most Christians lives here on Earth is far worse than those. They have to work, they have to deal with bad people, they suffer pain... Yet, almost all Christians really really try hard to survive. That is, they don't want to die.
You say you believe in Heaven and eternal life, but in reality, you don't.