There is a regrettable tendency in Christian circles to make too much of marriage and relationships so to correct the balance here's a collection of hard won wisdom on singleness. I call it hard won because I learnt most of these lessons the hard way and I call it wisdom because not a single piece of it is from me! All of it has dropped, like the proverbial pearl, from the tongues of others and it is all routed in biblical wisdom.
The Superiority of Jesus Christ over the opposite sex
The four great words to remember here are: no marriage in heaven. Well, that's not entirely true, there is marriage in heaven but it is the marriage of Christ and the church. This should remind us that Jesus should be first in our hearts for that's where he'll be when we're in heaven! It's good to keep this sense of perspective: human marriage is finite and only a picture of the eternal union of Christ and the church.
Likewise, Jesus died for your sins, he is your High Priest, you have no better friend, when everything is taken from you then through Christ you can still have lost nothing. Compared to your boyfriend/girlfriend/spouse, well, it's not a competition. You can lose a human relationship; you can't lose Christ, he will not allow it.
Don't make a relationship an idol. "My people have committed two sins: They have forsaken me, the spring of living water, and have dug their own cisterns, broken cisterns that cannot hold water. (Jeremiah 2v13) Don't dig a marriage cistern, keep in mind that God is the spring of living water.