You are correct that PMA is so hard to do when you are hurting so much. Fake it till you make it, I guess. I have a really hard time with PMA when I am around my wife. Just keep trying.
My W also changes her attitude fairly quickly. There is a recent post/reply on my thread about this that I think helps explain it. Head over there to read it. Take care and I hope things turn around for you.
M 37 W 36 T22 M14 D8 D4 8/2012 distanced BD 11/2012 (likely wants D. Feelings have changed.) W move out date: June 8th.