My first guess is that you have a unique home which may not suit the average buyer and you have probably been over priced. I can't know this for sure, but what you describe would be a common outcome in that situation.
I'd start by finding out who has been very successful in selling homes in your area. Ask two or three very good agents to come in and give you their honest opinion on the appearance, condition, marketability and pricing for your home. Ask them to be brutally honest and listen to what they say.
We spoke to a family a few years ago and they didn't like our advice, so the listed with someone else who told them what they wanted to hear. After a year and $100k in price reductions, as well as changing the things we suggested they eventually did sell. They stopped by an open house we had in the neighborhood to tell us they wished they had listened to us.
Fix whatever you have that is keeping the buyers away. It could be maintenance items, cosmetic or just poor marketing. Price it like you mean to get it sold. Your previous history will be used against you if you continue to over price. Freshen things up and take a different approach or you'll get the same results.
Best of luck and let us know how things go.