Personally, I don't know who/what did more damage to Tobias. Growing up without a mother who was supposed to be dead but was alive and abandoned him, having an abusive father who controls his mind and makes him fear his life, or having his girlfriend be lost to the whisper of a never-waking oblivion.
I want to thank you all for your support to my question. I agree as well. It only got worse, but at least Tobias got his mother back. I think if Evelyn had left with the factionless, and never came back, Tobias wouldn't have had anything to really live for again.
they all really hurt four but i think tris death was the worst because his mother leaving him and his abusive dad happened before he met tris and he lived with it and tris made his life way better but then she died which is so upsetting that i feel how hurt four is.
It all hurt but it all made him stronger in some way. Marcus made him physically stronger, but Tris death and Evelyn being so Evelyn made him mentally stronger. Without Evelyn leaving Marcus would have never abused him. So in different all of them made him stronger, and none of them hurt him.