Don't let them, Must.
I've already been told I don't need to commute in next week if I'm shaken. I will. Like wannabe said, we all take risks.
After 7/7, Ken Livingstone said;
"Finally, I wish to speak directly to those who came to London today to take life. I know that you personally do not fear giving up your own life in order to take others - that is why you are so dangerous. But I know that you fear that you may fail in your long-term objective to destroy our free society and I can show you why you will fail.
In the days that follow, look at our airports, look at our sea ports and look at our railway stations and, even after your cowardly attack, you will see that people from the rest of Britain, people from around the world will arrive in London to become Londoners and fulfill their dreams and achieve their potential.
They choose to come to London, as so many have come before, because they come to be free, they come to live the life they choose, they come to be able to be themselves. They flee you because you tell them how they should live. They don't want that, and nothing you do, however many of us you kill, will stop that flight to our city where freedom is strong and where people can live in harmony with one another. Whatever you do, however many you kill, you will fail."
I kept it because it spoke to me, and now I know it off by heart! Maybe it'll help you, too.