Dear Majo
about the wedding... not sure what to say. follow your gut. i went to the wedding of my once-best friend from high-school, sacrificing a grade point in a class for it - it was a butt-breaker class (computer architecture) with an even more butt-breaking teacher. my project partner decided to go off and do freako drugs so i was doing the final project by myself, and i knew if i took off for the wedding, i probably would not finish ...
i went to the wedding with bunches of printouts, pencils, markersr, and tried in vain to work on the project (wasn't really able to.) i didn't finish it in time.
my friend got divorced 3 years later - looky looky, the time required to get her residence in the US. when i invited her to come for thanksgiving she accepted, then bailed at the LAST minute, leaving me with no plans as i'd already turned down other invites. reason: she wanted to "spend some quality time" with her new boyfriend ... whom she married years later. (i chose not to attend this wedding... she kept throwing complications at me and i finally said NO.)
so see, ppl do what they want, and they screw you over sometimes without concern for your plight. you do what you want in regard to this wedding. if you feel like going, go. if not, don't.
A caution. If the main reason you wouldn't go is due to feeling offended about not being involved in choosing a dress and stuff, think very carefully about it. you might get over this "offense" later, and feel sorry you missed her day. my best friend got married and i wasn't there because of a similar reason. i told myself there were other reasons too, but really it was because i was offended that she told my room mate and me to sort out between ourselves who should be maid of honor. i was
so hurt. since she didn't "choose" me i told the other girl to go ahead. and i didn't even go. very soon afterwards, i was sorry. if only i had had the courage to let my friend know, then, that i cared that much about the role, and/or that i felt hurt, i could spared us the whole drama, spared her being hurt i didn't even show up, and been a part of her day as her maid of honor. Now i live with the regret of not having been there... oh we have forgiven each other and she is still my best friend... we talked about it long after the fact. but do not let some silliness spoil something big, is what i am saying here.
On the other hand, if it just feels like a duty and not genuinely important to you then don't go. you know, the fact you felt "offended" about not being involved in the dress choice etc
suggests to me it is somewhat important to you, even if you hate her boyfriend. What was this "offense" about, really...
did she hurt your pride, or your heart? that might help you decide...
-------------------
ok now rooming with someone i barely know would scare the daylights out of me.
then again i am someone who *always* wants their own room when i travel. i need to have a place to hole up because i do a lot of it. years ago maybe the hotel would have seen little of me but i am no longer that way, and nobody, not even company, can drag me.
i am not a power tourist, and several years ago when i made a trip on my own, and saw things i couldn't be bothered with, i had a *moment* - and right there i got over the world's preconception that just because you are in some great faraway place you have to try to cram in every possible sightseeing venture possible.
if i am going for a purpose, once that purpose is satisfied i am happy. and i will happily stay in the hotel and watch tv. i
will go out on a whim, do other things on a whim,
if and when i have the energy and desire.
also here you are talking 2 weeks... to see a band? usually a concert is not 2 weeks... so i am a bit confused. do you expressly mean to combine the trip for other activities?
anyway, i was thinking of your fibro and stuff, and whether you might have a need to stay in the room like i do, and do a bit less of that walking and walking and walking... that people often do.
either way, if you are seriously considering this and considering a roommate, talk to this lady very earnestly about how you intend to approach your vacation and what your needs might be in regard to the room. and ask her questions. you might also talk about some personal habits... 2 weeks is a long time. some ground rules might be good too.
i'm going to be blunt here 
, just to give you an example, ok? some ppl have no compunction whatsoever about bringing a "date" into the room to make out andthensome

. Some may not even care if a room mate is present. Others may have implicit expectations that the roommate will "take a hint" and leave... this is just one of many possible hazards of sharing with a total stranger, however nice she seems. i would make
explicit ground rules about guests (even friends), alcohol, drugs, etc... if you are really going to share with a stranger.
good luck with your decisions.
~ waves ~