I agree very strongly with James on this, but have something to add.
God has really been revealing to me recently just how great and enormous his love for me is and in that love, how much freedom he has given me to live from my heart. While I do not have the experience James does in the area of marriage, I completely believe that what I'm learning can be applied here.
I've always lived believing that I needed to hear specifics from God before I could move on something or make a decision. I didn't make decisions or take action on things because I needed to know what "the right thing" to do was. And I believe that God has a simpler, more love-based or heart-based approach for us to live in.
I too have spent much time in prayer on things, hoping, waiting and often fearing what God's answer may be. But if we are truly in love with Jesus first, we have the freedom of his love, grace and mercy. And in that there is peace.
My life is beginning to change dramatically as I am beginning to make room for this freedom that his love brings. I'm not just making decisions without care or thought, but I'm not requiring God to give me specific instructions on every little thing. I don't need to figure out what the "right" or "best" step is. I am bringing everything before God and saying, "This is what I feel. This is what feels right to my heart. Be with me here. Be with me as I do this."
And this I know from experience, that when we step forward WITH God and IN love with him, he will be there and his love, grace and mercy will abound.
Marriage is certainly a huge step and commitment and I'm not saying that you should just go after anything you want saying, "God, be with me in this," but more that this is not about "making the right decision." It's about your heart and your love for God. And his love for you!
This is just where I am in my walk right now and if there's something in this that seems good and right as you walk with God, praise God. If nothing else, simply continue to cast your cares on him. He is ALWAYS faithful.