I don't know anymore

Heads up its a little long.. So my SO and I had to move out of the place we we're in. I moved in with family and he moved in with a friend. I wasn't really okay with this but whatever you gotta do what you gotta do. So while he was living with his "bestfriend" our relationship went down hill really bad. His friend would always tell him to leave me and a bunch of shit is what my SO said with is why our relationship was the way it was. Well his so called "bestfriend" kicked him out two weekends ago during freezing weather.. What bestfriend does that and not even have a reason? I don't know but then he tells me he's going to move in with this guy from work. Remind you my SO had only had this job for maybe 4 months of that. So I'm like okay whatever, I mean you don't know him well enough to move in with him and I don't know this guy but sure okay. Well I went over by him and his friends place from work place. They are supper close. This guy went out and bought my man deodorant and a electric razor for his face. They share their money basically from what I've seen. I don't know how to explain it but it seems as if something is going on with them two. Remind you, when my SO and I lived together he didn't like sharing money and he would complain about buying me something but with this guy he just buys whatever for him and the other guy. So I asked my SO if he was maybe gay or something and he said no, when the other guy came out the room my SO laughed and told the guy "guess what she asked?? Are we gay!!" They started laughing but acted strange about it. His entire attitude has changed. Kinda in a good way. His really sweet to me now and really doesn't treat me the way he use to when he lived with his "bestfriend" or even when we lived together. It went from really bad to the next day when he moved I , really really good. Like out of know where. I asked about it and he said it was because the guy he moved in with was married and divorced. That the guy knows a lot and that my SO has talked to this guy about me and this guy "helped" him see that he really loves me and wants to be with me. Mhh okay sounds good and shit but really. You needed ONE day to change everything? Am I stupid for thinking if something like this or what?