I feel battered and not in a good and crispy way

I live with my girlfriend, lilacsigil, and have done for the last twelve years. I never came out to my parents about it. They don't talk about sex, ever. Not when I had a boyfriend, not when I had a girlfriend, not ever. Nobody is demonstrative in our family, showing physical affection is rare and usually awkward. I had a book pushed in my direction when I was ten and my little brother was coming along. I was cool with that, I already liked books much better than people. But no sex talk ever. So, I never really came out, and I felt vaguely guilty about just assuming that they assumed I was in a relationship with a woman, because, you know, maybe they thought we were just friends? Last night, I found out Mum was having visitors over - a woman whose daughter is gay, married and raising a baby in New Zealand, and I was worried that, I don't know, that she'd feel uncomfortable? That there would be weird silences because I've never formally said it? Suddenly this conversation happened:

Me: So, you know lilacsigil is my partner, right?
Mum: *laughs* Yes. I have known for some time.
Me: Right. I just wanted to make sure that we were all clear on that.
Mum: By the way, I went to a sex shop today.
Me: ...
Mum: With your little sister
Me: ...what?
Mum: She wanted a sexy cop uniform for a party
Me: Right...
Mum: They had so many things! You should go.
Me: *head explodes*

Then she told me that she was happy for us, and that she loved lilacsigil, and I remembered that occasionally my family is bloody awesome.

(lilacsigil, I love you more than books!)