Your DS is doing well to get through his health problems with your support and then a qualification and then hold down a job. At this life stage, it is important that he makes relationships with people of his own age. This is a complex subject. He needs to be going out to local events. Perhaps join a society for his favorite hobby etc. I do not know if you have a second lounge at home and encourage him to bring a friend home. Is he good at social media and able to use it to join in activities?
I need advice for a mutually messy situation
Things that (sometimes unreasonably) get on your nerves...hopefully lighthearted
best wishes, hope it work out ok for you all.