As time passed, more people became aware of vampires and drank tons of vervain, making them impossible to compel as well as to drink their blood.
Damon was going crazy. The frustration of the recently stolen blood bags from all nearby hospitals just made him want to snap someone's neck or torture someone to give him the lightest of drops.
Desperate times required desperate measures. Damon had to get blood somehow, so that's why he came to you. He knew you would the very least hesitate, allow him to after an argument if he was lucky. You knew how many cruel things he'd done, and it's not like you two were the best of friends at the time. Sometimes you were close due to the circumstances, and sometimes you just wanted to strangle him.
Blood sharing was intimate, you knew that. In fact, it was him who first told you when you became a vampire. But then again, he was desperate, and the thought of desiccating wasn't exactly his biggest dream. "Just a sip, come on. Promise I won't snatch your head out of your body," he says sarcastically with one of his mischievous grins.