Sonia Paz, a divorced 33-year-old single mother, jumped into the online dating scene about two years ago. “Being a single mother, I didn’t have the energy to go to a bar or club,” she said. “So I figured I’d post an ad (online). I got a response and it was great.” She dated and even met someone she fell hard for. Though she dated him for more than a year, she said he remained aloof and she felt as though she didn’t know him very well. When she mentioned this to him, she said he would respond with “cutesy” answers...