Working on other people that are negative?

I have a few people in my life that at the moment I cant not be around. My boyfriends best friends new girlfriend is one of them and obviously a few people at my job. There moods do not affect mine.. any more at least. Applying all of Brookes work and doing my own thought work I have over came many obstacles but now I would really love to help other people. I feel bad for them.

They are always complaining and negative. How do I got about speaking to them in a way they can see differently.
One I would really love to know just because I want to be a coach myself and two since they are people I always have to be around I would just like to help them be a little more positive for my environment sake.

Thanks for the life changing work!!!