recommend mc rejoining society after being jailed, isolated, etc.

You can try The Innocent Man :o)

Your very welcome :o)

• The count of  of Monte-Cristo: Great Revenge  (imprisoned) - havent yet watched this cause there are missing subs but if its anything like Alexander Dumas's book. This would be awesome.
• Legend of the condor heroes (secluded)
• Bride for 8 years (coma) - movie
• A story of a man (imprisoned)
• my husband Oh Jakdoo (lived like  hermit) 
• werewolf boy (wikderness) - movie
• A man from no where (secluded himself from people) - movie
• I am not a robot (due to severed human allergy)
• kimchi radish cuubes (was adopted and in a mountain monastery)
• Maybe
  • Terius bahind me (lived in hiding because of espionage) 
  • kingyo club (bullied and outcast) - highly recommend this
  • my id is gangnam beauty (bullied and outcast)

Don't worry about it, we all get those cravings, we are drama fanatics afterall.

I haven't finished i, more like saw the beginning only, but I think PRISON PLAYBOOK also fits your criteria.

• Hwayugi - the ML is a demigod who was locked up (under house arrest) for centuries as punishment for a misdeed; he persuades the FL to set him free at the beginning of the drama
• Thirty But Seventeen - as a result of extreme guilt related to a traumatic event in his childhood, the ML has many personality quirks that are related to his need to self-isolate so that he cannot hurt others; one of those quirks involves frequently running off to the wilderness (I think they may have said he does it every year?) and the first time in the drama that we encounter the ML as an adult he is out in the wilderness (the Swiss Alps if I remember correctly), and then soon after he returns to Korea / society; on a deeper level, the whole drama is arguably about him "returning to society from isolation" i.e. opening up and allowing people to get to know him without pushing them away or self-isolating
• The K2 - the FL has always been raised in seclusion + held against her will because she is the illegitimate daughter of a powerful politician (including in a convent in Spain at one point and under house arrest + surveillance in Korea later on); she tries to escape on several occasions; she also has social phobia due to a traumatic event in her childhood; the ML used to work as a mercenary abroad in almost-wilderness conditions; he is framed for the murder of his girlfriend and becomes a wanted man on the run; he returns to Korea and later seeks revenge against the people responsible for his girlfriend's death
• Moon Lovers: Scarlet Heart Ryeo - the ML is a prince but was raised outside of the palace by another family who held him as a human hostage; he was raised to be wild and ruthless, which earned him the pejorative nickname "wolf dog"; he returns to the palace at the beginning of the drama
• Are You Human Too? - the ML (Nam Shin III) is a robot created by a woman who was separated from her son (Nam Shin) and not allowed to see him; he was designed to look exactly like Nam Shin; Nam Shin's mother built Nam Shin III while living in hiding in Europe; if I remember correctly, it was the first day that the ML was allowed to go out into society for a field test that (through fate or coincidence) he crossed paths with Nam Shin right before he was hit by a truck and put into a coma; the ML then has to learn how to pretend to be the human Nam Shin and goes to Korea to protect his position while he's in a coma
• Mr. Sunshine - in the 1870s the ML, who was born a slave, flees Korea (running for his life / almost as if he's banished) after his parents are killed; he grows up in the US where he is mostly an outcast and very isolated (there are no other Koreans around him), and he returns to Korea as an adult; near the end of the drama he's also imprisoned in the US for several years before returning to Korea
• Sound of the Desert - the FL spent spent a few years raised by a scholar in a foreign court; she had to flee for her life because she witnessed a political coup; the ML and SML both meet her while she is living with a wolf pack in the desert and both fall for her (or at least they were both very interested in her from) the moment they meet her. (Note: I'm not sure how you'll feel about this one given your comment about unwavering love and FLs not distrusting the ML. The FL falls for the SML first and has a friendly love/hate relationship with the ML where he flirts with her and teases her and she sasses / teases him right back. It takes a while for her to fall for him and she always has a soft spot in her heart for the SML).