Does my sister respect me ?

My sister and i are both in our twenties. We lived together for a few years.Last night she went on a date with a guy she met at a BBQ a month ago. They talked on the phone 2-3 times since then. So, she went on date last night at 9pm and she returned today at 3pm. I tried to call her on her cell and she never answered.When she came home she didn't say hello.This isn't the first time she does that.She goes off with strangers. I always tell where am going or call her. Does she even care ? Her safety is in jeopardy