What rights do i have as a house sharer?

I have been living in a share house since 15 January 2011 and when I went to view the property it was asked if I could do a 6 month commitment. this however was not stated in the agreement I subsequently signed. it does stipulate that we each have to give 2 weeks notice. I have been a good tenant, paid my rent on time, did my bit to ensure life in the house goes smooth even after i was literally banned from having my post/packages delivered at my house. on several occasions a courier delivered my items out of the time agreed and in those cases my landlady would reject my parcels and I would have to re-order and have my parcels delivered at work just to avoid that situation. However last week Monday a family member of hers advised me that she fell ill and her mobility has been affected and they want my room back since it's the only bottom floor room. Although this lady made me promise not to move prior to 6 months the family argues they just need to give me two weeks. I do want to assist them but it's been hard, its been a week and I still have not found a suitable place. they refunded me my deposit to sort of have money to secure a place. i have spent so much now on looking for a room and most rooms are �25+ more pw than what I pay now. What are my rights? do I have any. i was literally told today they need the room by Wednesday coming and even that is against the two week notice period. Should they not compensate me for this HUGE inconvenience? i do feel sorry for the lady even though she was totally nasty with me but do i now have to sleep on the streets?