While the purpose of your life was suppose to involve investing in a marital relationship and raising children in the fear and admonition of the Lord (and you still hope it does), maybe the purpose for all living is simply to know Him, something that exceeds circumstances. Maybe true ministry to others, true purpose, doesn't depend on anything circumstantial, but rather believing that He is God and living out that growing knowledge of Him, being a witness of the One you love, wherever you are, even in the solitary passing of time. To know Him. Just simply to know Him. To grow in knowing Him.
Accept that, and even as you long for something more temporal, you can be content.
Quoting Elisabeth Elliot from The Savage My Kinsman:
"[T]o be a witness to God is, above all, to know, believe, and understand Him. All that He asks us to do is but means to this end. He will go to any lengths to teach us, and His manipulation of the movements of men . . . is never accidental. Those movements may be incidental to the one thing toward which He goads us: the recognition of Christ."Methinks perhaps that's why I'm still single.
"'You are My witnesses,' says the LORD,
'And My servant whom I have chosen;
That you may know and believe Me,
And understand that I am He.'"