Here's a thought on marriage. A marriage, or any relationship for that matter, is only as strong as its weakest link.
When the going gets tough it will only get as good as the weakest link. What do I mean by that? If only one partner is willing to take responsibility for his/her contributions to the relationship troubles, and (if necessary) seeks out the necessary guidance, and makes the necessary changes, there's little chance of this relationship holding up.
Whereas if both partners take responsibility for their contributions and are willing to put in the effort and action to make positive changes, big chance this will work out.

Just reflecting on my failed marriage.....

Bottom line, both need to have a desire to make it work. And take responsibility for one's contributions and attempt to rectify them.