What was the worst way you've ever gotten rid of someone you weren't interested in any longer?

It legit just happened. A guy I totally forgot about and had deleted their number out of my phone texted me. We were talking for awhile months back and I just lost interest and he fell off the face of the earth anyway. I pretended he had the wrong number and denied ever talking to him. Well he didn't believe me and ended up saying well have a good and honest life and left it at that.

Thing is I'm horrible with telling people I'm not into them or interested anymore and it seemed like the best way out at the time but now I feel like a jerk.