Rover 220 SDI turbo R reg - wont start?

I have been having a mare trying to start my car. been going on a few months on and off now and it is currently stuck on the drive.
When i try and start the car it just keeps ticking. The battery is charged and lights etc work fine. I have just had the starter motor changed (it started for a day!) but back to not starting now. Other people have suggested the alternator or relay...