I may have entered Depression / Resentment, but I am having a hard time recalling any feelings of intense love for her.
Yes sounds like you are in this stage. Depression, don't care about anything, have no love.
Are you eating properly, sleeping well, exercising? All could be signs of depression if you said NO. If you can't get out and GAL and start moving you might also want to think about some ST John's Wort or getting on some AD's.
I was never depressed but doctor said I had stress.(Ya think?) Same prescription for stress as depression. I went on AD's. No shame in that. They really helped.
You must take care of YOU. That is #1 job right now.