I at times find the pure desires of my heart turned into selfish desires. Then the battle rages. The desire to have God grant the desires of my heart. I seek, pursue, and refuse to allow them to go away. Is this wrong? Is there a time to forget the desires of our heart, to just let them fall away with no resolution? If they are no longer pure in intention, yes! How quickly I lose sight of my purpose. Anything that is not drawing me closer to God, is in essence wrong, because it's keeping me from experiencing everything God desires me to experience. "Sometimes God doesn't give you what you think you want, not because you don't deserve it but because you deserve more." Sometimes our pure desires turn into obsession and drive us away from our purpose. Sometimes we limit God by our desires and He calls us to dream bigger. Sometimes we seek to fill the void with things other than God and God desires us to know wholeness, and will not grant us these selfish desires.
Then you throw in the fact that God has given us free will. Maybe our desires are pure, and continue to center on growing closer to God, but these desires might hinge on other people. This gets tricky, cause now we may be pursuing pure desires and come up short. But God is faithful and will bring good out of any and every situation, IF WE LET HIM. That is the tough part. Sometimes we must wait and rest in the Lord. Don't get so busy that we fail to listen to what God is saying. Don't forget that it's a relationship with God, that it takes time, and that to imitate Him (Ephesians 5:1) we must study Him, spend time with Him, and pursue Him!