Of course there are many ways to handle this but one way would simply be to practice on another VC or four in order to get comfortable.
In the 90's I was able to get two different VC's to show up at my office. They wanted me to meet them at their office. I told them I was ready to make a decision and didn't have time. That I had met someone else and had an offer on the table. That only got them more interested.
It probably goes without saying, but this tactic should be employed only if it's true. One should never gamble his long-term reputation on a short-term bluff.
But in the end a gamble is a gamble and much of business is made up of chances where you bet correctly. Of course there is a risk. On the other side you can be totally honest and that has it's own problems, right?
Telling someone that "I had met someone else and had an offer on the table" isn't really concrete enough to be called a liar. Deals fall through all the time for many reasons.