I was actually thinking about mentioning that some women grope men as well, but I didn’t in the end. Wish I had, because now the usual thing has happened.
Nevermind that you didn't claim that women don't do it, either.
The starting point for this really needs to be that the overwhelming majority of women in this country have been sexually assaulted in some way in their lives and that the overwhelming majority of people who commit sexual assault are men. Yes, 'not all men' but fucking hell we're so beyond that.
From a male perspective yeah it's really fucking uncomfortable to look at yourself as a potential threat to a woman, particularly if you've always conducted yourself in a respectful way, but it doesn't come near the discomfort that women feel on a daily basis. The pulling your mates element is, I think, the main thing we need to focus on in this. There is still too much of the "wayyyyyyy LADZ" culture out there which is the basis for a lot of this behaviour. The silly twats beeping girls as they go past or catcalling, it's generally ignorant and puerile idiots who are just showing off. It can stop if people stop laughing at it, stop encouraging it.
We can unfortunately never eradicate the kind of monster who has attacked this woman, but that's not really the point here. It's about trying to eradicate those other behaviours which add to the discomfort and are done without thought of the real impact that they have on the person they're aimed at.
Make sure boys are taught to respect girls in school and that unwanted physical contact is not ok and pull up your dickhead mates and grow up a bit.