1. If you speak at conferences, especially about a non-technical subject like "women in FOSS projects" (which is more likely to get sexists riled up), you are going to get unwanted attention. Pretty much every speaker who speaks on a controversial, or non-technical, or just media-glamorized topic is going to get harassed - if not hacked. It happens all the time to men and i'm sure it happens to women.
2. She started a "geek feminist" website, so that didn't help in terms of getting some sexist asshole's attention. It's like starting a "geek black people" website and not expecting white supremacists to send hate mail. I'm not saying it's justified, only that you have to expect the assholes out there will come out of the woodwork to give you shit.
3. I need to do something that feels rewarding and fun, and the work I was doing - which involved lots of speaking at conferences wasn’t giving me that any more. - So stop speaking at conferences? The tech industry has more going for it than giving talks.
4. If the guy isn't posing a physical threat, suck it up and ignore it. Do you know how many people troll me every week? A lot. But I make myself a target - just like being bullied in school - and thus I need to defend myself or move on.
5. Stop trying to 'get more women in technology'. Why is this seen as a serious problem that needs fixing? Go ahead and work to reduce sexism, I think that's necessary because the internet tends to reduce everything to childish unprofessional behavior. But nobody's code is going to get better just because there's more females working on it. Instead, focus on improving the tech industry as a whole instead of one little facet of it (like the distribution of gender).
I'm sorry if I sound unsympathetic. I do sympathize. A friend of mine stopped working in the underground infosec community because he was putting out a magazine and people were sending him hate mail. I understand he didn't want to get shit, but he had to expect haters - it's the fucking internet.