Hey Willo sorry to hear about the hassles, it can really knock your confidence for six.
Having been glassed, teeth fractures and having my eye knocked out of its orbit it's a real bad feeling, but don't let them stop you from having a life, or disturb you for too long.
Kto lit areas (preferbly with CCTV around) and if nessicary cross the road well in advance of any dodgy looking characters.
As for martial arts here is what I have found :
judo you have to get in too close
Karate etc, you hurt yourself when you hit/kick people, and leave yourself open to assult charges
Akido is about the most useful, both legally and physically, as it's defensive only assult charges are very unlikely, plus you don't hurt yourself as you don't hit anybody.
You should bear the assult business in mind as I ended up with a GBH conviction when removing my brother in law from the house while he was being abusive towards my son (then 8 years old) and myself.
Admittidly I did thump him twice (well what do you do when a 40 year old man calls your 8 year old boy a bar-steward and worse, then won't leave the house). However when he grabbed me and I pushed him off, he went over on his ankle, and broke it. I was judged to have been irresponsible for pushing him off me and was found guilty of GBH.
Provocation dosn't appear to be examined in the court system these days so please be careful. This has resulted in having to cancel family plans to emigrate to Australia, and my job hunting prospects are fu**ed for the next 8 years.
Don't let yourself get into the same (or worse) position by carrying any perceived weapons, or getting all medieval on somebodys ass (even if they do deserve it).
Be aware at all times, and look after yourself,
Rob...