I don’t think him being depressed is an issue here. 28 year old not having a job and living at home should be enough warning that he isn’t dating material. In addition if he has no job asking to live with you pretty much asking if you’d take him as a so called “kept” man. Those are all major red flags. I honestly wouldn’t worry about why he is how he is but look into patterns of why would you choose someone like that? Is there a pattern? Do you oftedste people like that? Do you try to save them?