Does my husband truly love the OW?

My husband left me and our two boys about 3 weeks ago and moved in with the OW and her 2 kids. I am not sure how long they had been talking, but do know they did not spend much time together, if at all, prior to his leaving. She lives an hour and a half away as well as work that far away. So now he lives with her and her kids and will post on Facebook that he loves her. .. loves her to the moon and back... calls her lil nicknames that he called me even till the day before he left. Does he truly love her or is it just the newness and infatuation of it all? I guess in all honesty it doesn't matter as I am filing for the divorce on Monday side he made it clear (before I knew about her that he was done and was not interested in trying to work things out. He had left and I didn't know why until I found her number and messages on his tablet when the boys were watching monster trucks) that there was no working it out or working on us, but I just can't see how he could move on so quickly and call her the same pet names he did me. I know I shouldn't bother worrying about this since I am taking the steps to move on, but it still hurts to hear about his feelings towards her.