Hey hold on there just a minute. First of all, have you been speaking with Bocete? Secondly does Gorn know about this? I mean we haven't even been properly introduced. Then there is the ring. Does it have to be a diamond? And what about the kids? How can we ever agree on what religion we are not going to bring them up in? And lastly but most important, who gets control of the remote?
Okay here is another analogy for you. I am happily married to the same woman for 34 years. I am more madly in love with her than i ever have been. We are totally open with each other about who we are and what we are thinking. I know she is my soulmate and the the best thing that ever happened to me.
Gorn doesn't believe in marriage. (poor Gorn how did he get dragged into this?) He says I can't prove that I love my wife and that I would be just as happy without her or maybe happier. After all, he says I am a good man and I would be a good man without her too. Why should I have to tied down to just one woman who has so much power over me? There are plenty of other great women. How do I know I wouldn't be just as happy with one or all of them? Not tied down to any one woman.
I tell Gorn that yes I can't prove that I love my wife and I can't even prove that love is anything more than a biological response. But I also tell Gorn that I was with a lot of other women before I met my wife and none of them captured my heart like she did. I tell him that it would not be logical for me to turn my back on my wife that means so much to me, even If I can't prove that I love her. Besides I couldn't do it anyway.
Okay, I think I get your analogy. Just using your analogy, it sounds like you and this fictional Gorn agree, logically, rationally, but you love your wife (not Gorn) anyway and don't want to stop. Fictional Gorn might point out that what you're feeling is brain chemistry and he'd be right and you'd agree but that doesn't matter to you.
I think you said that your wife and your love for her are good for you, they make you happy, and you think you're better with your wife than without. As long as that's true, then I don't see any problem.
If that were not true, and instead, your wife is a compulsive gambler and you spend your weekends robbing banks to pay her debts, then, even that's not illogical if that's how you want to live your life and you're okay with your likely death by cop. It's only illogical if you claim that you want to live your life without hurting others too.
So, then, back to the original question "does logic matter if it doesn't change the way I live?" I think the answer is yes and no. Yes, logic still matters and it's frequently wise to use it when you make decisions, and even in this case, it's probably smart to recognize the facts, but for this decision, the logic doesn't matter to you. You just like Jeeps. It's a preference.
The next analogy has to use pepper!