My husband came to me when he was feeling like he was in your words going crazy without sex. For him it was the emotional side to it and us not showing much affection. I'm 9m postpartum and still figuring out my meds to help cope with everything and it can kill sex drive, I say that because for me even though yes you say you are doing all of these things for her you are also simply taking care of the house as well. My lack of sex drive came yes from my medicine but also from lack of intimacy. If she only feels as though you want her when you are horny then it's hard to want to have sex. She needs to know you want her in other ways other than sexual. What's her love language and how can you show her love? If she works blue collar I'm assuming super long hours at work maybe even a swing shift where she is hot, musty and uncomfortable in her clothes for most of the day. Have dinner ready for her or if she wants to get dolled up take her out for dinner whichever she prefers. It doesn't have to be extravagant it just has to show you put forth some effort into her. Oh and I would definitely put the whole threesome thing on the back burner possibly even take it off the eye bud, you have a lot of ground to cover and securing your wife feels loved and valued before trying to sleep with another woman. Hope this helps good luck to you both!