Get the bike and don't go. Maybe your folks can offer to throw a "welcome home" party for them (nothing fancy - just a chance to get together and share some snacks). That way you're still supporting her and the marriage, without spending a boat load of money.
I don't see why you should sacrifice to enable what appears to be a fiasco in the making. (Of course, I've been called grumpy in these situations. We went to the last one with the BIL at DH's insistence. It was as bad as I feared. I hope the lesson has been learned - but I doubt it.)
ETA: On further reflection, maybe separate the bike from the decision to go. Would you not want to go anyway? Then don't go. What you do with the extra money is up to you. I wouldn't look at it as an if, then proposition (nor would I share that with your family).
Last edited by Blueberry; 06-14-2012 at 07:34 AM.
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