She Has No Idea

My wife and I have been married the better part of 3 decades. We've had out ups and downs but for the most part things have worked out well.
Sex has always been good. Even when she's not in the mood she usually let's me have my way with her and I always try to reciprocate.
She gives great blowjobs but rarely lets me cum in her mouth and on that once in a blue moon occasion when she let's me, she spits it out.
I've asked her to swallow but shes refused.
She usually says stuff like I should "just be glad that I let you cum in my mouth sometimes." Or...
"Theres no way I'm eating your cum!"
What she doesn't realize is that she has been eating my cum since we got married!
The wife is a weekend drinker and usually gets really horny after a few drinks.
Her favorite drink is a 14oz cup of White Russian.
After a couple of those she usually stripped herself naked and begging for a good fuck.
I always start with fingering her to a good orgasm before I mount her. By then she always wants a refill of her drink so I grab her cup and head to the kitchen.
In the darkened kitchen i quickly stroke my erection. By this time I've usually been edging for an hour or two.
The thrill of doing something sneaky is a big turn on and as I feverishly stroke away I can no longer contain myself!
I grab her cup, now refilled with ice and hold it to the end of my aching penis.
I orgasm and shoot my load into it!
I slowly work my cock from the base to the head wringing out every last drop of semen into the bottom of the cup.
After a moment of recovery I finish mixing her drink, stirring it heavily and then top it with a lid and straw.
When I hand it to her, she always takes a long hard drink.
She has no idea of the bonus ingredient.