First thing I would do is discuss with the listing agent that you are not a happy client and request that they release you from your listing agreement. Second If they do not release you I would then go to his boss / manager / broker to explain your situation and request that you be released. You really need to first go through the official steps to get a release.
If you want to go with the new company & agent, I would not want the old broker to "assign" me a new agent. I would be up front and just ask to part ways on happy terms. If you approached our company and me in this manner I would gladly let you walk (knowing what little I know).
The normal listing agreement is 3-6 months with maybe 12 being the absolute longest for high dollar homes. In todays market a 6 month listing is not unrealistic, 12 months or more in my area is extreme unless it's a luxury property.
Do not file bankruptcy unless absolutely necessary. Talk to your new agent about a possible short sale that will allow you to walk away from the house. I believe I would let it go into foreclosure before I filed bankruptcy (unless you have high amounts of other debt) Banks today are eating a lot of homes and unpaid mortgages.
Have you ever listened to Dave Ramsey on the radio or internet ? He has a lot of good advice for folks in your situation and much of it revolves around real estate.
Check him out at:
Real Debt Help - Get out of debt with Dave Ramsey's Total Money Makeover Plan.
Best of luck & keep us posted after you talk to your agent. BTW, I am hanging out in Boston this week visiting our 1st grand child. These cools summer days make me want to make a trip up your way to buy for a summer place to live. Although you can keep the winter cold, this sure beats our summer TX heat.