LW1: This reminds me of a crush I had as a high school sophomore-- there was this senior I was madly "in love" with... I followed him everywhere. He regarded me as nothing more than a casual friend. I wasted my time and made myself look like an a$$. In your case, this guy is married-- that means (or should mean) he is not available to you-- even if he were interested, which it doesn't seem that he is. Stop going to this dog park.