Brother-like friend no longer has time
Just a suggestion. When someone asks you about what you do, maybe say that you are in between jobs at the moment but have been gardening peoples yards. That can give someone an opening to ask you more questions.
I had quite a stressful job. It took over my life. There were times when I couldn’t maintain friendships as I was busy during the day and exhausted at night and on the weekends. Don’t take it personally. I’d give him a little space for now. It can be difficult to be a support person and they do need time out too and go back to focusing on themselves to get that energy back.