Paired lines is an annoyingly frustrating thing. You share a copper line with the house next to you. If they get adsl 2 you can't and vice versa. Things like this are first in first served so when the previous people moved out, your neighbours would have snapped up the port. Only way around it would be to run a new copper line to your house. That can get pricey for the home owner. I remember speaking with alot of people who were in new estates being built that had the same issue.
All you can really do is keep applying every 6 months or so to see if theres a port available or perhaps look into a mobile internet option depending on how much you use/plan to use. Theres some good devices/antennas that can extend your signal strength/stability as well.