Depends on which country you got married in, but afaik most of them are recognised here so you can get a divorce here in normal UK way.
Only thing to watch out for is if you've married abroad then redone it here - apparently some people worry that their foreign ceremony won't count, so redo the service here, then get the latter undone, but are technically still married because the second service wasn't recognised because the first service was and you can't get married twice (if that makes sense).