I think in Mormonism, JWs, and Islam there is marriage in Heaven.
But Matthew 22:30 says:
Since the Bible seems to teach that sex must be within a marriage, no marriage means no sex. Some see sex as a gift from God and might miss going for an eternity without it.
What do Christians think?
There is no marriage in heaven.
1Co 15:44 It is sown a natural body; it is raised a spiritual body. There is a natural body, and there is a spiritual body.
Gal 3:28 There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for ye are all one in Christ Jesus.
Mat 22:30 For in the resurrection they neither marry, nor are given in marriage, but are as the angels of God in heaven.
The only thing that separates a man and a woman is the flesh but the soul and spirit are the same.
Which they will put off the flesh and have a glorified body which is the same.
Which they will be like the angels in heaven which angels do not have a gender but they are only known as having masculine names for they are greater than humans.
Isa 65:17 For, behold, I create new heavens and a new earth: and the former shall not be remembered, nor come into mind.
Rev 21:1 And I saw a new heaven and a new earth: for the first heaven and the first earth were passed away; and there was no more sea.
Joh 14:2 In my Father's house are many mansions: if it were not so, I would have told you. I go to prepare a place for you.
Joh 14:3 And if I go and prepare a place for you, I will come again, and receive you unto myself; that where I am, there ye may be also.
The saints and angels will remember nothing prior to the New Jerusalem and will feel like they were always there and nowhere else.
People will remember nothing about the earth and will not remember their spouse.
Heaven is spiritual and not for marriage.