Weddingbee boards

Ok, so I've been through 4 months of wedding planning thus far without turning into a bridezilla, but I'm definitely bordering on it at this point.

When my fiance proposed I asked one of my closest friends to be my maid-of-honor. We went to college together and have been friends for a few years now. In the past, she has always been helpful when I've needed her. She told me that she was really excited, came shopping with me a few times getting wedding ideas and stuff... and then her enthusiasm fell off the radar. 

More recently, We invited her to come camping with us and a bunch of me and my fiance's friends - about 40 people (whom she doesn't know). I suggested that we could use free time while camping to work on wedding planning, like picking a bridesmaid dress (because she poo-pooed all of the dresses I had picked out previously and then tried to convince me to let her buy a dress that looked more like it was from Sex in the City than for a garden-themed wedding). She agreed that we should do that. I packed all my wedding books/magazines for our trip. She then informed me a couple days before the trip that she wasn't coming until a day after us, and that she didn't have a tent. So, we brought her one of our tents, and even set it up for her. When she arrived, she didn't even say thank you. She just asked what there was to eat and drink. She didn't bring her own food/drink and was planning on getting drunk on our dollar and eating all our food all weekend. When I told her that we didn't bring enough for her to, she promptly took off to another campsite and hung out with different people (who offered to feed her). I Hardly saw her all weekend. I was told that she had gone into our coolers while we were sleeping, and she ran around in a string bikini all weekend (even at night) and basically totally embarassed me. My friends kept saying, "Seriously?? THIS is your MOH???" I was mortified, if for no other reason than I know people will be snickering about her behaviour at our wedding.

So anyways, I had a 'talk' with her about her behavior after the trip.I told her that I expected her to behave like a maid of honor (in general) and that when she was meeting our other friends, I expected her to behave 'appropriately' and in a way that was flattering for her. She said she would, but hasn't changed her behavior. The weekend after that she asked me what I was doing that weekend. I told her that I had a bunch of stuff to get done for the wedding. She told me that she wanted to go boating (my fiance has a boat) and that if we change our minds and were going boating, that she would come with us (Told me - not asked me). I had another friend who offered to come help me instead, and then while we were working on spraypainting birdcages (etc), my MOH started sending me texts messages asking when I would be done doing 'wedding stuff' because she wanted to hang out with me. I told her I didn't have time to hang out, because I had to work that evening, but she could come help us. She instead chose to wait at my work for me to get there, and then told me that she'd driven past my house multiple times that day. (That was a total slap ing the face to me - You'll drive by and pester me all day but you wont just roll up your sleeves and help out??)

Anyways, I had another talk with her that day. I told her that I suspected that while she wanted to help with the wedding, was not really interested in the workload that comes with the title of MOH. She responded by telling me that she had 'good news'. She had decided that she was going to be to wear a dress that I picked out (and offered to pay for) because even though she didn't want to have to look elegant (I kid you not - she said those words!), that was the type of sacrifice she was willing to make for me.

I could continue with the selfish, self-absorbed things that have happened, but I think you get the idea. I really dont think that she wants to be my MOH, and I have reached a point where I don't want her to be the MOH, but she denies this and says she will 'try harder' and then does nothing.

To make matters worse, no one else will join the bridal party with her being the MOH. 

I cant explain how frustrated I am right now and I am afraid that if I don't kick her out of the Bridal Party that I will resent her and end up destroying the friendship.

Also, I forgot to mention previously, about a month ago she asked for one of my friends phone numbers after we'd all hung out one night. The next day my other friend showed up at my work and was pretty ticked off -- She had texted him 136 times in a 24hour period. He has now 'forbidden' me to give out anyone elses info to her (which should make for another awkward conversation if she tries to plan a shower).

Help! Does anyone have any comment, advice, or suggestions?

@Miss OBG: Prior to our camping trip, I had never seen her around  a group of men. We had only girls in our college program, and usually when we hang out it is one-on-one. Also, to clarify about her 'switch' in behavior, I suspect that it has something to do with her breaking up with some guy she was 'seeing' - We discussed her change in behavior and she told me that she just 'want guys to be looking at her'. Aside from the fact that she is flaunting herself in a way that makes her look cheap, I'm concerned that she will be 'looking for attention' at the wedding too.