I haven't done a formal survey, but based on what I have seen, 95% of couples that ride together just ride their own bikes. A tandem sounds like fun to me, but given that my wife isn't interested in riding, period, it's kind of out of the question.
So clue us in here. Does "Group Rides" mean the hammerfest from hell, or an assortment of people meandering down the road or does it mean a charity ride or what? Does she get mad because everyone else is slow or because she gets dropped or because y'all holler at her or what? There's lots of potential issues that could come up. Anyway, if this is the group ride as in a paceline situation, don't be afraid to go on different rides where y'all can do your own things, especially if you like different speeds or distances.
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"be careful this rando stuff is addictive and dan's the 'pusher'."