Sayid says he doesn't deserve Nadia

In the flash sideways, Sayid is fixing a broken vase after a boomerang incident. Then during an emotional conversation, Sayid offers to pay Omer's debt, but Nadia tells him that Omer must resolve his own problems.

Nadia asks him why he doesn't want to be with her, since he carries her picture around with him. She says that Sayid pushed her towards Omer. Sayid says that he's spent the last twelve years trying wash his hands of the bad things he's done. He ends saying "I can't be with you, because I don't deserve you."

So in this timeline, he still has deep regret about the acts he performed in the Republican Guard (presumably that part is generally the same), but his depression seems to be deeper in this timeline.