I am just trying to understand, how I can fix this so it doesn't keep happening. please let me know your thoughts

Recently my boyfriend has picked up a side business and he always goes to his friends house after work to hang out, like everyday he will leave and be gone for hours, and I'm okay with it but after so much I'm starting to get annoyed, like the other day I didn't feel good and my head hurt so bad I was in bed crying and he said he would be right back and he didn't come home for four hours, and he will hang up on me and walk away from me now which is new behavior because he use to not be like this. If I call or text him to check up he says I'm being controlling and that I don't need to know shit until he gets home and then we can talk about it. He will have a huge melt down and act like his life is doomed if I ask him to just spend time around me for once and put me first. I don't understand  where this is coming from, he use to text me all the time and we use to talk not I feel like there is constant tension in the room with him, and honestly all I want is for him to show that he still loves me, now I'm questioning everything, but then he turns it around on me, like I did something wrong for being concerned. I can't even have a normal talk with him to resolve our differences he just shuts me out