
You probably know this already http://www.mangago.zone/read-manga/At_the_end_of_the_road/

Therapy Game! Minato is one of the best written ukes ever. I love him so much. It has a prequel called Allergy XXX and XXX Secret. The prequels aren’t as angst, but Minato is first introduced then and so is Minato’s lover, Shizuma.
http://www.mangago.zone/read-manga/therapy_game/
http://www.mangago.zone/read-manga/nirameba_koi/ (No trauma, everyone just thinks he’s a gangster)
http://www.mangago.zone/read-manga/minori_no_te/ (High school lovers who fell apart and meet later. Seme is cold though)

http://www.mangago.zone/read-manga/mods/
http://www.mangago.zone/read-manga/wolf_in_the_house/ (Second couple)
http://www.mangago.zone/read-manga/iberiko_buta_to_koi_to_tsubaki/ (second couple)
Not super traumatic but kind of sad backgrounds:
http://www.mangago.zone/read-manga/i_have_a_boyfriend/
http://www.mangago.zone/read-manga/castle_mango/
http://www.mangago.zone/read-manga/lie_cry_like/
http://www.mangago.zone/read-manga/sensei_mou_dame_desu/

http://www.mangago.zone/read-manga/cupid_ni_rakurai/ Not a really dramatic trauma but yeah...
Any bl mangas where the uke is cold and had a sad childhood or any kind of trauma