Hi there. You mentioned Mt 7:21, that's the very text our pastor preached on this morning. I found that I have it cross referenced to John 6:40, perhaps there is the answer God is giving you: Look to the Son! You ask,"What book, sermon, prayer, is there??" Friend, I suggest you don't look for another book or sermon but to the Saviour Himself. What you are looking for is in Him. What you need is in Him. As for, "what other prayer is there?" the answer is thanksgiving and simple, childlike asking. For Him to lead you to the right fellowship. For Him to help you to love Him with all your heart, mind, soul and strength. For Him to teach you to pray, to know Him, to be willing to obey and surrender all to Him. I pray you will find rest in Him. All is well because Jesus has overcome.
I've been dealing with the same thing for a long period of time. I really feel you, it's really hard. I wish some person that had the heart and filled with the holy spirit would give an answer if there is any... As you mention, I also feel like I dont have the love for Jesus enough, I dont care about other people and I dont wait for Christs return with hope & eager. Every day is a struggle and often I come to the point of giving up. I wish things were different, but I feel helpless.
I will be praying for you, dkr777. There is no temptation that is not common to all men. And, we all must persevere during those "dry" seasons so that our leaves will not whither. May you be encouraged by the words of Psalm 1 and Jeremiah 17-18. And, be encouraged that God knows you even better than you know yourself. Rest in the assurance that God will not despise those who come to Him with a broken and contrite heart (Psalm 51). Seek...and ye shall find.