I sometimes have single guys seek advice on whether they should propose to their girlfriends. A few have even lamented that they can’t decide whether they should marry or break up—which is a strange dilemma. If one is an option, the other shouldn't be.
If you are dating someone and do desire marriage in your life, though, those actually are the only two options that make sense long-term: either you are moving towards an eventual marriage, or you are moving towards an eventual break-up.
So how do you know which one it is? Here are some questions that might help you decide whether you should get married.
Are they (and you) fully committed to Christ? If so, it should be evident in every area of the person’s life. Someone who is committed should be a member of His bride, the church; be known there and growing in biblical community; and be serving Him with their time, talents, and treasure. God created marriage, and it works best when you have two people committed to following Him first and foremost. (2 Corinthians 6:14)
Are they (and you) willing to fully commit to each other? Consider the vows you will make: things like “in sickness and in health, for richer or for poorer, till death do us part.” If anything other than death is a potential deal-breaker, you really should include that in the vows: “till you cheat on me with my best friend do us part.” You can be certain that troubles will come, and the only way to ensure your marriage will last is if both parties commit to it no matter what. (Mark 10:9)
Do you have the approval of other committed believers around you? Do those who know you both best think it is a good idea? This is one of the reasons why it is important to be in a community of people who know you well, have your best interests in mind, and are yielded to the Spirit and God’s Word. (Proverbs 15:22)
Would they make a great spouse and parent? There are roles each person plays within marriage. Do they fill these roles well? (Ephesians 5:21-33)
Do they have good character? Have they demonstrated themselves to be trustworthy? Do they do what they say they will do? You are trusting them to keep a pretty big promise when they say “I do.” (Luke 16:10)
But what if they might not be “the one”? You know, that mythical unicorn-riding soulmate who is perfect for you in every way? They aren't “the one” until you choose to marry them. There is not just one, but many people who potentially would make an incredible spouse for you. You are simply looking for someone who meets these criteria, and for whom you can answer “yes” on the above questions. You then create “the one” for each other when you both choose to commit to each other for the rest of your life.
Fact is, you’ll never find anyone who is perfect. And that's good, because you're not. And though it certainly helps if you share common interests or have similar personalities, those are nowhere near as important as the items listed above. (Plus, it is difficult to support that biblically when the Bible was written in a time of arranged marriages.)
You need to be able to live with them in an understanding way, care for, and cherish them. If you know you can't, break up.