She never did before we were married.
In fact, she didn't like me going down on her at first - but that soon changed... :naughty:
Now, I almost always do it for her.
As for me, she didn't suck me off at all for years - it wasn't until we'd been married about 15 years before she did at all. She was molested as a child and that's what the boys from down the street made her do, so she's always had a problem with it.
So, I've waited patiently for it. She has to be in the right mood to do it, but she's gotten better at it and seems to enjoy it more.
The real drawback is that she can't get all of me into her mouth - the head fits (barely), but she can't go down very far: it hurts her jaw. She's learning to lick up and down it, though... :biggrin1:
I'd say I get sucked once or twice a month, but there are times when she'll do it 3-4 times a week.
It just depends on her, and I've learned not to force the issue.