Hiya. Single mum to DS7 here. Have been a single mum from pretty much birth.
Dad has a new partner who he has been with for a number of years. I have gone out of my way to be friendly and inclusive, we have group facebook chat for arrangements, I get her birthday and Christmas presents, etc. In return I am treated like an inconvenience.
They now have a child together, DS7s half sibling.
She has on her Instagram profile that she is a 'Happy mother of two boys!!!' and so help me god I have not been able to rest about it. She is NOT MY SONS MOTHER. But nobody else thinks this is weird. I tried to raise it with Dad and he shrugged it off and said I was being sensitive.
DS7 later told me that she has told him to call her Mummy as it is apparently 'confusing' to his half-sibling (who is not old enough to talk......) if he calls her by name. I am incensed.
AIBU? He's MY SON.