Hey miss Abigail, great questions!
I used to think of myself as waiting on God for a husband, and honestly I was miserable. I had built marriage up so much in mind, it was almost like an idol. I got so depressed waiting on God to bring about what I felt He "owed" to me, because marriage is a great thing, right?
Sure, marriage is great but it's not the reason I'm here on earth. God asked me what I would do if I never found the right man to marry, and I realized I was putting all my earthly hopes into a dream that may never come to pass. I couldn't live like that anymore, and asked Jesus to be my everything, marriage or not.
I'm SO much happier now.... I focus my time and attentions on what I know God has called me to. I'm still very much open to marriage but it's no longer my primary goal or focus. I'm trying to seek my place in God's earthly kingdom and trust that if marriage is in His plan then it will come to pass. Of course that will require some effort and discernment on my part. But I'm just saying that kingdom living brings its own joy and purpose, whatever gets added to that is an awesome bonus

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As far as keeping thoughts and actions pure, I try to focus on what God DOES want me to do, rather than what He doesn't. Not a complete fix but it works pretty well for me personally. I realize it is probably more difficult or complicated for those with different backgrounds, newer to the faith, or just different brain wiring. So please excuse my oversimplification, I'm just sharing my own experience!