DD (yr 3) has a best friend and they often have sleepovers/after school playdates etc. They get on brilliantly - never argue, always laughing etc and she's a very sweet girl. Her mum however tends to blank me! For instance today I was stood next to her at school pick up, I said to her "alright?" but she didn't even glance at me - I'm pretty sure she knew I was stood there. Also tonight I dropped DD off at her club and she was chatting to another mum near the door so I had to walk round her and she didn't acknowledge me coming in or leaving. If I start a conversation she will chat but that's about it. She's the opposite when texting as she is always very friendly, and the same when we're collecting/dropping off our DDs at each others houses. I just find it strange that our DDs are so close but she barely acknowledges me and doesn't seem to be like that with others. AIBU?