Shutterbug...short of moving to another city..I don't know how you could have a gurantee that you would never see him. Statistically, you probably won't but--I don't know where you can get an insurance against it.
If you should see him--look away, immediately and get off at the next stop. That is what I would do, anyway......
Addiction hurts everyone it touches, that is for sure!
dandylion