Your phrase "mutual love" is key here. Love has to be mutual. Both parties have to commit to each other for life, and swear never EVER to leave each other, NO MATTER WHAT. In order for "everlasting mutual love" to be possible at all, both people need to never to give up on the relationship. NOTHING can tear you apart. Your relationship cannot be easily broken, or else anything can and will tear you apart. You need to honor your marriage vows. They are not suggestions. They are vows that should last your entire life; literally, "til DEATH do you part." It's serious stuff, and it's the most important decision you will make in your life.
But lots of marriages fail nowadays. Why? Well, there's TONS or reasons why, and we cannot know all of them. But the key issue is that one or both parties have decided to give up on their marriage, and decide that they didn't really mean their marriage vows when they said them. The basic issue is: someone gave up. For whatever reason, they stopped fighting for their relationship.
So I think that, in order to find true, everlasting love, you have to be with someone who is willing to commit to being your "everlasting" partner in life, and who will never leave you or forsake you.
Now, I do think there are times when it is good & correct to leave a relationship or marriage. If the person is abusing you (or especially your children!) physically or sexually, then you need to get out of there until that person is willing to get help and change. You need to put your children first in this circumstance and protect them.
And I don't think that it's always wrong to get a divorce. I think it's undesirable, and unfortunate, but sometimes better for both parties involved.
Divorce sometimes enables people to gain back their lives, become whole again, and move on to better things. But divorce can scar children forever. Divorce can rip families apart and put people in dire financial straits.
Those who've been married for years can tell you that they decide everyday to put their spouse 1st and protect their marriage.