Charles when Erik got freed.
The second he saw Erik, he punched him directly in the face.
"SHE DIED BECAUSE OF YOU. NOTHING WILL CHANGE THAT."
Erik had a bit trouble getting up, but he knew Charles was right.
You were married to Erik during the fight against Sebastian Shaw.
Erik thought you were strong enough to help fight, even though you told him you weren't ready. He didn't listen to you and all that he cared about was killing Shaw.
Charles was the only one back then who actually cared about how you felt about it. He was the only one who tried to get you to a save spot when you were bleading, bleading to death.
Erik was so busy with putting a coin through Shaw's head, that when they told him you were dying, he didn't give any sign he cared.
That was when you realised Erik wasn't the one for you.
Charles was.