Try cocoon of the heart
Its angsty for most part i think cus its more towards the unstable state of the uke n some fluff scene along the ending
Hmmm not sure but the main couple didnt cheat or anything, they were kinda like enemies in the beginning but the seme finally falls in love with the uke after knowing his side of the story
Its the side characters i think that may be cheating or having an affair
Recommend some angsty manga/manhwa/manhua pleaseee. Preferably weak/sickly uke EXCEPT 10 years that I loved you the most