65 [M4F] #Maryland - I'm trying to figure out if it's me or the ex that can't finish the task

Wife of 30 years left over 4 years ago. She has been back helping the daughter with our first grandchild. Staying at my place and we started having sex. It's pretty good, but it's very difficult for me to cum. I'm trying to figure out if it's in my head or her technique. I didn't have a problem before we split. The past 4 years I've been hooking up with women younger than me. Getting older sucks and while the med I use works wonders. It can desensitized my cock a bit. If you think your cock sucking skills are on point and would like to prove it. I'd love to borrow your mouth for a test.

In the name of science of course? 6'2" 240 dad bod. Average in the pants,.Very discreet, open to more, but not a requirement.