That took far too long. Domestic distances are from the AA route planner and European ones from the site The Chimp linked.
Away games from when staying in Aberdeen = 1647.8 miles (there and back)
Away games from when staying in Dundee = 880.8 miles (there and back)
Home games from when staying in Dundee = 1356 miles (there and back)
European games:
Aberdeen - Amsterdam - Kiev - Dnipro = 3570.95
Dundee - Glasgow - Brussels - Madrid = 2759.43
Aberdeen - London - Munich = 1942.62
= 8273 miles (there and back)
which is a total of about 12,158 miles