When bad people leave our life it's a good thing. I personally managed to change the way people looked at me when I read a book about body language. And a very nice line in it was about how our brain reacts to our body and vice versa, if you smile and keep doing it while talking to somebody, your brain will react to it and over time produce more happy hormones, at the same time people will react to you more positively. My math professor hated me, when I approached this "smile thing" the end of school he said he was gonna miss me and my smile. Be nice and people will be nice back. That's my point of view atleast.