Eternal Marriage

Some people have the belief that marriage unites people so that they are together forever in eternity. So far, so good. However somewhere along the line this belief deviates and becomes a discontent alienation and an egotistical significance complex. (With all due respect, this is not intended to offend anyone and I am only discussing around the concern that aroused)

When it comes to mormons, also known as members of the LDS church, an Eternal Marriage is held in the sacred mormon temple unifying the love of the two souls into one in eternity.

In regards to this belief, a man can remarry if the wife dies, which means conciling another soul to the allready existing unity and in other words the man can have two or more wifes in the afterlife. As such this could be interpreted as betrayal to the previous wife who passed away and is doomed to eternal marriage without being able to change this because she is in fact: dead!

Another concerning aspect is that non-mormons are not allowed into the temple. In the example I came across, a whole familly was left out because they were not of the same nature and declined the offer to convert. This makes me wonder whether the mormons are simply striving for an egotistical significance separating them from the rest.

What kind of a religion would not allow familly to be apart of the marriage? And why does the non-mormon familly still have to show up for important pictures, happily outside of the temple?