That's really tough. I can't believe his parents would put him in that situation. Yes, the father should get a place of HIS OWN if he really feels he needs to leave. Why would he ask his son to move out of his apartment and take care of his mother? If he were that concerned about the mother in the first place, he wouldn't be looking for a way out for 6 months.
They have put their son in a horrible position, but I don't think that makes him a bad person, or should jeopardize you staying with him. If he does feel like his mother is having mental health issues, and needs someone with her right now - although it would be irritating to you, it would be nice of him to be willing to do that.
~ the artist formerly known as babywavy ~
Please excuse any typos. For the time being, we are blaming it on my computer.