Wow! You two sound like my wife and I in reverse. She says hurtful things that she regrets and I pull back until there is a gulf between us wider than the Grand Canyon. Having witnessed the pain and sadness in her apologies (though, we still do this crap), I really can feel for you. Sometimes our thoughts just come out without going through any of our filters. Hang in there! If she is serious about you, she will come to understand that what you said is out of character because you are not a hurtful person. She's just hurt and, I know, that hurts like hell. Don't beat yourself up! You made a simple mistake and hurt somebody you love. You care because you love her and because you are decent. So, give yourself the grace you seek from her and the grace that you would give her. Forgive yourself. You're not a bad person, you just used poor judgment for a moment. That makes you human.