Please help me try to convince my wife to do sleep training in any form. She is miserable from lack of sleep but feels "too guilty" to let our son CIO.

Our son is 8 months old. For 3 months now he's been sleeping terribly. He's easy to get down at night but he doesn't stay asleep more than ~90 minutes. It started when he learned to crawl but it never got better. He doesn't self-soothe. If my wife doesn't nurse him back to sleep he wakes up all the way and we all sleep less. Naps are inconsistent, he takes 2-3 depending on the day ranging from 30 mins-2 hours.My wife is miserable from lack of sleep. She has frequent headaches, she cries often and easily and is constantly snappish at me. She's had 3 colds in 3 months. I take shifts with her but I also have to work so I can't take all night every night for her (I would if I could).We were both opposed to sleep training, believing it's a milestone reached in his own time. However, we've reached our breaking point. My wife WANTS to sleep train him, but she can't bring herself to for the following reasons:She is a SAHM and thinks she should just deal with the sleep deprivation.She worries sleep training is cruel on some level and we are not meeting our son's needs by leaving him to cry.We are overwhelmed by the different options mixed with all the advice. For every method there's a dissent, and always looming is the possibility that it's harmful for the baby or that we're forcing something on him that he's not ready for.These next two are the big ones:A. There is a free sleep consultant at our health station who recommended Pick Up, Put Down. She said that leaving the baby to cry is NOT recommended and that we shouldn't do it. This is the country's "official" stance. We tried one night of it and our son went apeshit. It was not his "I'm pissed" cry, it was, "I am being murdered." Went on for over an hour. Not sure we can do it again.B. Our son is a very happy baby. Always smiling, not afraid of strangers, constantly playing and exploring. We seem to be the only ones suffering from his sleep habits. He wakes up beaming every morning.What we do:Solid bedtime routine.Cosleep.Pacifier.At this point I will take anyone's thoughts or critiques. I don't want to manipulate my wife into anything, but she is suffering and I want to make a case for sleep training in ANY form. via /r/Parenting http://ift.tt/2cYEGGt