God specified there will be no more tears in heaven (no more suffering) once you enter heaven you will be happy for ever, you will walk streets made of gold live in mansions and worship god FOR EVER, the thought of your loved ones burning for ever is a sad and depressing to think about but with the comfort of god you will be happy.
Half the point of the bible is that we have a very limited understanding of what things are like after this life. Besides, do you know how many times the bible has been changes? There's every probability that what we think we know about heaven and hell is completely wrong! Yes different religions believe differently, but even other Christians will debate about how it happens. But the remaining factor is that all 3 of the most practiced religions in the world believe that their god is good and merciful. So no, we don't know how it's going to go down but I'll take my chances with heaven. Hopefully before I go I can make sure my loved one's will meet me up there eventually.
You seem to misunderstand Heaven.
When we reach Heaven, we will be in the presence of GOD, the Almighty, the really Big Guy, the One and Only, our Creator, the Alfa and Omega. When we get there our minds will be so focused on Him that even if we know that some of our loved ones are not there, we will be happy that we are in the presence of our Lord.
Remember, we should love God above all things, that includes family. (and I'm not saying that a person should neglect his family)
Do you think God will let you be sad in Heaven? How about children with parents in hell? How about marriages where only one person believes in God? Do you think God has not thought about this? Do you DARE to question God?
Repent from your sins and accept Jesus Christ as your savior. When we get to Heaven, then you will find whether you will be sad or not.
John 3:16 - For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life
1 Corinthians 2:9 - But as it is written, Eye hath not seen, nor ear heard, neither have entered into the heart of man, the things which God hath prepared for them that love him
Everybody has a different opinion on what you have to do to get to heaven so most people are going to hell if one religion and denomination is right. Heaven would be like hell for me if i had to watch my family burn forever. Id end up getting put in hell myself because i would hate god. Eternal damnation for not believing in something that cant be proven is ridiculous. Especially when it has no evidence. Why would god prove his existence to some and make some of us incapable of believing. Dont you know its hard for some to succeed and easy for some to succeed. Its hard for some to conform its easy for some to conform. Some people are smart some people are dumb. None of this is said to be their faults. We know that stuff isnt their faults. But when it comes to good and bad and believing in something people think we all have an equal chance to believe and be good. Its ridiculous. If i had your brain i would do what you do and believe what you believe most likely. There is no evidence that suggests otherwise. But how can someone enjoy heaven without their family. Just goes to show you how selfish and non empathetic believers are.