I will be praying for you both brother. You are not being selfish in your desires for your wife. But it sounds like there is healing needed in her, and she's not being open on what's really wrong. Some women like men to pick up cues and guess how to help them from the cues (the you should know me by now perspective). Tell her you need her to be open and honest with you about how she feels and what she needs, because you can't figure it out on your own. And if when she does share, own it, don't justify any wrongs, just own and fix it. It can build up walls when a person has opened up and no progress was made. It may take time for those walls to come down, but they can if change is visibly being made. And remember, the amount of time it took to build those walls, could be just as long to tear them down, but as that person had to be patient through the process, the love and patience has to be returned.
I agree about seeking counseling, immediately! And if she declines to go, I would be open and honest with her about what you are saying to us, in all the detail. Don't feel like you are protecting her by not being completely honest and open. That actually brings greater intimacy with some women. Not opening up can do more harm than good. And if she still declines, I would suggest letting her know you're going to talk to someone anyway for godly counsel and support through this because its opening a foot hole for the enemy ( suggest a Christian leader/Pastor, minister, etc that you can trust...someone mature in the faith).
I commend you for seeking accountability and support on something so personal. Satan loses a point there, he definitely didn't want you to do that. He's going to send as many temptations in your path as possible, so think it not strange when these fiery trials increase. Stand your ground in the Lord! He will have your back. And great will be your reward.
Also, be sure when you do talk to your wife, that you listen to how she wants to be loved. People have different love languages (highly recommend looking it up, seeing if she'll read the book with you)...meaning you may need affection (Physical touch) from your relationship and think that will bring her happiness too. But she may like Acts of service where you help clean the house without being asked, or you take care of a responsibility she normally does without prompting. etc. Once both parties understand how their partners need to be loved, both have to commit to do them consistently, and without constant reminder for it to have its greatest impact. Trouble happens when one doesn't, and the other does. Or when one tries to use their love language to please the other and neglect their partners need. But, that's where a mediator can hopefully help you if it comes to that.
Again, blessings to you for seeking guidance. Don't forget to be just as open and honest with her as you were here. If you're too uncomfortable verbally, than write it. Its important she knows these details. I will be praying you both have an ear to hear one another, and God will grant you both understanding of the other and help you be on one accord.
As far as her not wanting to read and pray with you. I would gently remind her of the scripture that shows the power of going before God together Matthew 18:19-20.
Hang in there, you have back up prayers!
Sorry this is so long. And, I didn't proof read, so hopefully it made sense.