This might be fine but it's getting me down a bit so thought I would see what other people think. I've been with my DP for nearly 4 years. We have one DC each. Although we don't live together, we spend plenty of time together and we both get on well with each other's children.
When we are around his DC it is like I don't exist. Now I'm not expecting attention as of course the focus should be his DC, but I just feel completely invisible. He hardly talks to me, he won't sit next to me, he won't touch me. There's no quick kiss or hug hello/goodbye. He will however do these things when it's just my DC around.
He sees his DC very regularly, and they have huge amounts of time together without me around. We all spent the day together yesterday and I noticed just how obvious it was. His DC was smothered in kisses, hugs, conversation all day long (which is great), but it was literally like I didn't exist!
He gets very defensive if I bring anything up so I'd rather not have a conversation with him if it's perfectly normal behaviour!