Me too!
I find a bit of planning makes it easiest to overcome the loss of desire. Here is the strategy I worked out.
First, during foreplay, I ask my wife to pinch my nipples. Then when I am ready, I position her on the edge of the bed and get on my knees to eat her. This also gives me great access to rim her and the nipple play also makes me want her ass so much more. Then before she cums from oral, I fuck her. She always obliged by more nipple play that makes me cum with very little motion at all.
Even before I have finished with the last spurt, I drop to my knees and start eating. As the urge wains, it is too late. My desire to bring my wife to an orgasm overrides my loss of wanting to eat cum. I often lick the leacking cum off her ass and when the desire remains strong, I will rimm her using cum as lube.
Finally the post O blues sets in and I get a mix of feeling that always result from that. Any negative feelings are balanced by the pride I always take in bringing my wife to a great orgasm. After cuddling for a bit, the pride is the strongest and the negativity is replaced by being happy that I ate the cum and looking forward to doing it again.
I have never gone so far as to lick up any of my drippings on the floor. But for sub guys, licking your own cum from the floor is a great way to show what a cum eating slut you are.