Getting told that I have to "always" be positive

You know, I'm tired of having to be positive and hide the bad stuff, even if it is the truth, when we have new employees come on board. The HR lady just told me that I was negative when I told a new hire that it could take a month for his uniforms to come in. She said " it never takes that long". Funny, I thought I was the one who did the ordering and receiving.....