And this is just me, but no past traumas that revolve around a deceased love one. I am tired by cheap fridging/deceased love one = motivation in fiction.
It's not just you. Most of the LIs have had some sort of either parental or relationship issues, usually involving someone dead. Just looking at the ME games alone:
Steve--Dead husband, PC helps him get over it.
Samara*--Okay, so it's a bonus LI, but she's got daughter issues and blames herself. Has to kill one of her own kids.
Liara--Mom was working for the bad guy, and she had to kill her.
Thane--The ultimate hat trick of misery. Dying, dead wife that was due to his job, estranged son.
Miranda--Daddy issues doesn't even cover it.
Jack--Enough said.
Tali--Seems to be estranged from her father, and her mom is dead.
I'd argue that Ashley, Kaidan and Jacob (in ME2 at least) were the most "normal" of the bunch. And even then, Jacob's personal mission involves his dad doing terrible things to others. Yeah, enough is enough already!