you’ve been together a long time and have children I assume she couldn’t care less how big you are “your perfect” and to her the whole notion of making your dick bigger is crazy talk.
me… I made it a jovial conversation over time, my partner’s 15 years younger than me so I used fear over my erection quality, ED and felt I was shrinking with age as motivating factors and it was to be a fun experiment, hobby kind of thing, and the purpose was to increase my self esteem and no other. (What’s the harm)
think of rational reasons that might make sense to her.
Start by introducing a pump (I did) let her get her head around that first.
obviously I don’t know you or your wife but it honestly worked for me.