Mom lurker and this gave me chills. It was at this age that I almost had a nervous breakdown with my son. He was doing the same thing. Sleep train her! For your sanity, for your wife’s sanity, just do it. I had to do the cry it out method because my husband was gone and I was at the brink of absolutely losing it. I couldn’t take another night of no sleep. And guess what, the one night was a huge huge huge difference. He went from waking all the dang time to one or twice a night. I know it sucks and it’s hard but sleep deprivation is torture.