Most ships that sail from UK ports do not include transport to and from the ports but some like Fred Olsen, NCL etc do include coach transfers from Central London. Many offer free parking, but the only cruise line I know that includes transport is Travelscope but it is by coach. They sail mostly out of Falmouth in Cornwall, but its a long way from Aberdeen to Falmouth. They do have some dates where they sail from Greenock, Dundee and Liverpool. Fred Olsen also have cruises departing from Scotland. You can always ask the Travel Agent to arrange Rail travel.
Try princess cruises on sea princess and limited grand princess cruises leaving from southampton they include FREE coach transfer from local pick up points including scotland worth a loo.
We cruised from Southampton to the Baltics with Celebrity Cruises on the Constellation in May,we flew from Aberdeen to London and then celebrity provided a coach to the port at Dover we were met at the airport by one of celebrities reps. regards Iren.