Baby mama drama

Hey everyone. I've been dating this guy for a few months now (9) and I recently met his kids (the 6 month mark)

Well his baby mama is so cold towards me and I didn't do anything to her. They have a civil relationship which I think is good. But my boyfriend introduced me to her and I went to shake her hand and she rolled her eyes, told him to make sure one of the boys did their homework and to have them home at a certain time then she smiled at him, scowled at me and left.

Do I just keep my distance? I have no intention of being her best friend but a hello would be nice or something. Thoughts