As long as you're not under contract with her, you can do whatever you wish.

You absolutely can. You may even want to find a smaller broker that will allow you to sell on your own if you find a buyer yourself - then you can list your home on some "for sale by owner" sites yourself and maybe save on agent commission!

Yes you can but you must also be careful to make sure that you didn''t sign any type of contract with the previous realtor. If not then you can use any other realtor if you wish but if you have signed a commitment contract with him or her then you may want to read the term first.

See how long the commitment period is for? If for another 6 months and you cannot bare the sight of the same realtor, talk with the Realtor and cancel the listing with the realtor. You are allowed to take your house off the market. Then simply find another agent or setup interviews with at least 3 agents. Check all your options.