Work: Living in Faith or Fear. Please Pray

I realize that as of late, I've posted several prayer requests, and I worry about posting too many, thereby sounding like a selfish complainer.  For that reason, I try to post prayer requests that I think are important. 

I have a problem with work.  My parents keep telling to watch what I say at work.  I'm already trying to be so careful about what I say at work that I almost don't say anything to anyone!  My Dad has also cautioned me to watch what I say around my co worker.  (The other people are not co workers to per say.  They are teachers and I'm a Custodian.  However they can get me in just as much trouble.  Which is something that has happened to me in the past.) 

The problem is My co worker is probably the closest thing I have to a human friend outside of my parents.  He's a real talker, and we seem to share common interests.  As far as Christianity goes, He says He's a believer.  There is good reason to have doubts about this.  He uses some four letter words sometimes and I know He drinks beer and never goes to church.  But it is not my place to judge someone's salvation.  I just do the best I can to be friendly and live out the way I think The Lord wants me to Live. 

I'm scared because I know how co workers can be.  I have experience where several have said things about me that got me into trouble.  Like my Dad says people tend to look out for number one.  I've been praying: Asking the Lord to protect me and help me not to say anything I shouldn't around my coworker, teachers and whoever else.  But living like this is don't feel right.  It's hard for me to be mindful of everything I say and still be living in faith instead of fear.

I'm not looking for opinions.  I just want you to pray however the lord leads to you pray.