Welcome to the site.
I am Dr. Kaushik and i believe i can help you with your query.
Well you are well justified in your concerns about the future management of your son's condition because you see after rigorous treatment, re-entering a hectic and demanding lifestyle can again put a lot of stress on a recovering bipolar patient thereby compelling him to slip back into the clutches of Bipolar disorder, so therefore both the points that you have mentioned such as your son getting back to a demanding job immediately after the outpatient treatment is over and secondly him choosing to stay alone where no one is present to keep a watch over his symptoms and behavior so as to prevent any sort of deterioration or relapse , both of these need to be looked into keenly and some sort of consensus needs to be reached with your son to cater to these valid issues.
You see it is the period immediately after treatment which is to be keenly followed and monitored because it is the time when the person has recovered to some extent but is still not in the perfect state of mind to deal with the demanding and stressful lifestyle and a similar scenario is going to crop up when your son's treatment gets over and he tries to re-engage himself in his stressful and difficult job as this may act as a strong stressor which shall cause relapse of his condition.
So i reckon that first and foremost you need to ask him to take some more time before re-joining his job or still better will be to find a job which is not so stressful and demanding, if this is not possible then at least former option should be looked into.
Secondly you need to convince him to stay with you for at least 1 more month after his treatment is over so that he is under the watchful eyes of yours and recovers well and after that you make sure that you and other significant family members keep in regular touch with him and visit him often so as to gauge his behavior and activity in order to monitor his recovery.
You see when you mentioned that it takes time more than 6 weeks to manage this disorder, you just stated the basic fact about bipolar disorder and in order to achieve this you got to carry out above mentioned actions with your son's help and involvement as his active participation is going to be the mainstay for his full recovery.
I hope this helps to bring things into perspective.
Wish you all the best.
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