The caged thing really resounds with me, and your answer about her being happy if you are to be happy together is the answer to this issue too. She's holding herself back because of her guilt, which will take her time to get over. I think you might need to back off of your desire to get your R back to where it needs to be until she's healed enough to get there. Show her that you want her to do what she needs to to be happy more than you need to be comforted. She's clearly made her decision about the M, if you take her word for it - which is all you have right now. Run with it.

Maybe you should ask her what she thinks it's going to take to get the marriage to where she'll be happy with it. Details, don't accept answers like "time". She's got to have some idea short of escaping everything, which seems to me the mindset she's still in. The whole cage thing is important.

“No problem can be solved from the same level of consciousness that created it. ”
– Albert Einstein