<human>: Can you summarize the given text in a few sentences?

Probably not much interest in this question here but this is the situation.  I'm pretty pissed, think I have a right to be, but don't know what to do.

Months ago, set up a camping trip with an old friend, "Ken" for this coming weekend.  We are old roommates and currently do something like this once a year or so.  It's always been just the two of us.  Now, last night, two days before leaving, he tells me he's invited his brother-in-law!

WTF.  In my book that's insensitive and rude.  I have some social anxiety issues, which he is (should!) be aware of, and am not exactly loving the idea of meeting this dude and hanging with him for 48 hours on what I thought was a peaceful canoeing trip with an old buddy.

  After trying to think it through and looking at it from several perspectives I'm still pretty upset.  I thought, well, what if he'd asked first, would it be okay?  The answer is still not really but I'd probably be polite and say yes.  Or if he called me and said hey I'm going with this dude, do you want to come along?  It would really depend on the weekend, and this weekend I don't want another person there.

Other possibly relevant facts:  1. I planned and set up this trip.  2. It's his birthday weekend, but that doesn't usually mean much to us. 3. I've never met this brother-in-law.
<bot>: Plan trip with old friend, he invites brother-in-law at the last minute, not the vacation I was looking for.