I need advice plz

I am going out of my mind right now. My boyfriend of 16 yr just asked me last night if we can bring another female in to our relationship to spice up our love life . He was calling her my future wife. He is telling me that our love has gone down hill in the past yr . So I will tell you the back story . My boyfriend lost his job 2 yrs ago and just started to work again. I pick up more hours to cover the bills. I work 7 day a week anywhere from 50 to 84 hours a week. So when I get home I am exhausted. I do all the house work and take care of all my pets. We don’t have and children yet even though we have been trying for a few years. I have pcos so it makes it a lil harder . Getting back to my point I work a lot and coming home to him playing on his ps4 and smoking marijuana. By the time I get to bed it’s already 11:30 PM and I have to be to work for 6 am. All I wanted do is sleep. He will try to get me in the mood but I am already half a sleep. Am I being selfish? Should I let someone else in? I want to make him happy but I don’t want to lose him at the same time. What should I do