I'm the MOH for a couple of friends of mine (they had a 'fight' over whether I'd be Bride's side or Groom's side lol). I love them both and the MOB just cracks me up - she's an absolutely joyous spirit. MOB and FOB pretty much eloped (so she never had the big wedding that she always wanted) so she's living vicariously through the bride - and that means planning BIG.
Here's my dilemma: the bride's family is pretty well off, so MOB is sometimes like a 7 year old playing dress up with a credit card. She's talking about all of these visions for all of the wonderful pre-wedding parties - 2 bridal showers, 2 lingerie showers and a bachelorette getaway (in Vegas! No, wait, Mexico! No, Jamaica!!!) and (since she's never done any wedding planning before) she's asking me what I'm supposed to do and what she's supposed to do. She's such a sweet lady (and loves throwing parties) that I don't really have the heart to tell her that all she's really supposed to do is show up and smile, while I know that it's not financially possible for me to plan even /half/ of what she wants for her baby girl.
I'm planning a shower and bachelorette party (that will probably have a lingerie shower aspect to it - unless I get a lot of uproar here about how a lingerie shower is a lingerie shower and a bachelorette party is a bachelorette party and neither the twain shall meet! ;-) ) So, what is a polite way to tell her that I really can't afford to throw 5 parties (especially since my husband recently lost his job, and I'm a student as well as working full time)? And, obviously, I'm not going to ask the other members of the bridal party to pay for throwing extra parties that I can't afford to contribute to.
Re: Over exuberant MOB
The next time you two talk tell her what you are planning (are the other BMs helping? If so have you asked for their input/budgets?). And let her know that since you are planning these parties that you can't help her with her parties. But you never know the MOB may just want to help you out and then you could plan together.
If this MOB wants to pay for a ton of parties, let her enjoy.