Burn Notice, Season 3

Michael:
[Voiceover] There's no greater luxury in the field than working with a friend you rely on. When you find someone you can trust absolutely, you want them on every operation you do, and nothing hurts worse than losing a friend to bullets, politics or something personal. But when you have to work alone again, you lock those feelings away and do the job at hand, because as every spy knows, there's time to think about what you've lost after the mission is over.