Since when does salvation nullify a marriage? It doesn’t.

A Christian who is married to a non-Christian is a valid
marriage if that is what you are asking.

If you keep reading through 1 Cor. 7 you will see alot
of excellent verses that are rock solid for marriage foundations.

1CO 7:10 To the married I give this command (not I, but the Lord): A wife must not separate from her husband. 11 But if she does, she must remain unmarried or else be reconciled to her husband. And a husband must not divorce his wife.

1CO 7:39 A woman is bound to her husband as long as he lives. But if her husband dies, she is free to marry anyone she wishes, but he must belong to the Lord. 40 In my judgment, she is happier if she stays as she is--and I think that I too have the Spirit of God.

I need specific examples as that what you are talking about
on the other stuff. I am not sure where you are looking. Can you
post some examples?