There are no guarantees in life. Divorce aside, you could get married and have your spouse die, get sick/injured, lose interest, buy NFTs, etc. Marriage, like life, isn't about what you get out of it, it is about what you give to it. Do you love your gf? What are you willing to lay on the line to give them the best possible life? Getting married is, or should be, a complete surrender of yourself for your wife, your children, and the future of humanity. Do you think your gf would want out of a marriage where you are dedicated to her and to your children? Total self-sacrifice is tough to commit to, and it will pull more out of you than you knew you had, but it is also the only investment that will lead to contentment and a happy death. Choose wisely, choose life, choose love.