You often feel guilty in your relationship and are always looking to repair the “damage.”
It's not abuse if one genuinely SHOULD feel guilty and if the "damage" was, in fact, inflicted by that same person. Snape called Lily a Mudblood, therefore he inflicted the damage and DAMN RIGHT he should feel guilty.

I tell you, there's hypocrisy all over that thread, but it sure as hell isn't coming from a fictional character who's initials happen to be L.E.