Honestly, I don't think she ever would have.... the same goes for if Damon was in Stefan's position and he chose to save Elena first. The thing is that Elena really would do anything to save those she loves. She's made it very clear that if it came down to saving her or one of her friends/family, she would rather they be saved instead of her. Had Stefan saved her first and Matt had died, Elena would never have forgiven him because she wouldn't be able to forgive herself. She has already lost so many people and she would have blamed Matt's death on herself.

It's STEFAN we are talking about. No matter what he does, Elena will always forgive him. He doesn't even have to apologize properly, she's all & perfectly fine with what he did. Hypotetical scenario:
Elena: Why didn't you save Matt?! He died because of you!
Stefan: Oh... I should have saved Matt. But I Love you too much.
Elena: OK.
*Hugs & kisses*

I'm not sure...She forgave Damon for killing HER BROTHER. It's hard to understand her logic.

She always forgive him.

Damon didn't killed his brother. He tried. And it was different. Eitherway Elena can forgive both of them no matter what.

I think she eventually would forgive him, after some long time, but I think she wouldn't be capable of loving him like she did before. And Stefan would be crushed. I don't want to see him like that, so I approve his decision to save Matt first.

It would probably take some time, but in the end she would forgive him.

Then she wouldn't be a vampire.

She'll forgive him but not love him, trust him, the way she does now. All her feelings would be different.

She would have forgiven him because she loves him, but she never would have gotten over it.

she forgave damon for killing jeremy