Husband problems

K • Married, mother of 4 and pup
We've been together now for almost three and a half years. He's been working for this company now for almost as long. We've had to move twice in the past 9 months because of him getting promotions. He's told me that it was against company policy to associate with "lower" employees, considering he's a manager. But within the last two months, he's fb friends with 22 of his employees...all but 4 are girls. Now he's all the time on his phone texting or fb messaging with them. And it seems like he doesn't even care that it's causing issues with how I feel. I've tried to explain to him how it makes me feel, and he just turns around and fb friends more of his female employees. Am I stressing too much? Or should I be concerned?