Sounds like his depression is untreated, or his meds aren't working. I have depression. It took me about 5-6 years to find the right meds. When I did I felt like a new man. I had more energy, I was more positive, and I was so happy I just felt normal. I think the first thing he should do is get on the right meds. Try lithium. It's cheap, generic, a chemical element the brain needs, and it's effective. No side effects like all these new meds. What is he taking now?
When I wasn't on the right meds, I still felt tired a lot, and very unmotivated to do much of anything. This sounds like his problem. He knows you are a good person, but he has an illness that saps his motivation. Try to understand, this is not the "real him".
I think there might be a blood test for low lithium. Also have his vitamin D checked in his blood. I'm also on 4000iu of Vitamin D each morning, and that has made a difference also.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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