Only to an extent. It has to be proven that you took measures to separate yourself from the aggressor. If the aggressor continues to invade your "space" then self defense can be invoked.

The problem is... Evidencing this. Accessing the evidence that supports you. Not having a corrupt court system. Or a judge that wil move the goalpost if you do manage to prove effort was taken.

This is why Europe has a lot of those weird "bumping fights" where no punches are actually thrown, it's more a stupid chest bumping, shoulder barging "ooh ooh" Monke fight.