Wife: Honey, Jenny is having a baby shower XYZ weekend
Wife: Let's go
You: I hate showers and have no interest in going.
That would have put her in the position of trying to convince you to do something. Instead, you're in a position of trying to convince her that you shouldn't have to.
My actual advice: If you want to go, go. If you don't want to go, don't go. But don't set the precedent now that your wife gets to make all decisions for you just because you want to please her. Of course you want to please her, as that's your job as her husband. But that road has to go both ways or you are going to be miserable. If you don't want to go, say "Listen, honey, I need to tell you something. I really don't want to go. Showers are not fun. Do you REALLY need me there?" You then do whatever she says. But at least you've made your point and it's clear you're "taking one for the team" and not just doing what is automatically expected.