Baby Mama... I Don’t Want Drama!

I’m going to try to keep this short. I’ve been dating this guy for right at a year. We both work at a bar and the mother of his children frequently comes in( if the kids leave something at his house, get money, or just a girls night with her friends). They are working on effective co parenting and I think that’s great. The only thing is, over this past year, until recently, she hasn’t known about him and I dating. She has suspected, and from her suspicions, I have been bumped into, looked at crazy, attitude, etc. I have an interesting temper, so I’ve just stayed out of the way from her, because when we reach the point of meeting the kids, my temper and attitude won’t be the problem, if problems occur. I spent the night at his home last week and that morning she came over which is something she’s never done, and there ended up being slight drama. Not between her and I, but between him and her. Comes to find out, she’s asked about he and I before, and he denied that we were dating. I guess my concern is, when she suspected he and I were dating, she gave me a cold vibe, I’m curious on how her attitude towards me will be now that she knows, and how to handle it. Or what boundaries to set between he and I. Like, if she’s coming up to our job, she needs to let him know, and he needs to let me know, just so there’s no opportunity for drama. Has anybody else dealt with baby mamas? What have you done to just keep it peaceful and avoid drama and harsh feelings?