When trust breaks down in a marriage, the marriage itself often follows soon after. Trust is a crucial component of a successful relationship, and it is often impossible to build back up when it is gone. The event that took it away will always be there, no matter what either one of you says.
If this happens, even before you end the marriage, experts note that it can turn you into a "distancer" while your spouse becomes a "pursuer."
The way this works is that you lose trust, so the connection between the two of you breaks apart. Your spouse wants to repair it if possible and keeps pursuing you. However, since you do not trust your spouse any longer, you just keep trying to put distance between the two of you.
This often becomes a "destructive cycle" that you and your spouse can't seem to end. When your spouse tries to draw close to you, you redouble your efforts to create space. That only makes your spouse work harder to bridge the gap, so you work harder to move away. These movements are emotional and mental in most cases but could also be physical.
The problem is that since you can't trust your spouse, you don't want to repair that relationship. You know it is beyond fixing. Your spouse, with nothing to forgive since you did nothing wrong, thinks it can be fixed. When you're not on the same page, a resolution is very hard to find.
If your marriage eventually deteriorates to the point that you need to get divorced, take your time and look into all the legal steps you need to take to protect yourself.