I'm but a layman when it comes to interpersonal relationships, but it's my understanding that society puts pressure on people to get married. So while yes, in theory, you can be in a relationship and not married, in practice the social pressure will eventually push you, or, much more likely, the other person in the relationship, to want marriage. So your only recourse is to jump from relationship to relationship and break them off each time an ultimatum is reached. Breaking off relationships takes an emotional toll on people, so it's not a viable strategy for many people.

Marriage and love is the closest thing we can get to Faith in these secular times.

If you can't have Faith in another person, there's probably something deeper wrong in your soul.

That's not the end of the world, but it's worth exploring since it's low-hanging fruit for psychic development.