Ex calling DD by the same pet name uses for new GF - AIBU?

[EmmaRoid]

Pretty much as per title - it has come to light (Ex DP, DD father) has been using a pretty generic pet name for both DD and the new GF.

I do not think or believe anything untoward in itself, but the fact he fully aware how she feels worthless it makes me upset he has allowed her to find out the pet name is not "special" to her.

I have lost sight of what is reasonable these days due to history of abuse (from him and spilling out to being witnessed by the children), and a recent death in the family has me barely able to function past faking it for the children. DD has medical diagnosis which leads to life being more complex for her than most.

I made clear the issues DD has as set out by NHS including anxiety and self destructive behaviours and how fragile she is - yet this has happened and I am tired of defending him in effort to minimise the damage as this affects our relationship also. I want to just break contact, but never sure if for the best as she wants him in her life despite the damage/upset it causes.

For my DS (older and remembers more) he would happily move away and cease contact with his dad. He has said this on more than one occasion. DD still wants her dad to be her dad.

Am i being unreasonable to see this as a massively disrespectful (the calling them by the same pet name), and to defend DD as an advocate - as she is just refusing to look at her messages from him for the past few days and being teary/not eating (she is upset, but in a silent, but disappointed way but it comes out in withdrawal from day to day life) or am I unreasonable to pull him up on allowing a situation to occur where DD is left upset and set an ultimatum of not happening again and to move contact supervised?

I do want to highlight again she is more fragile than most children her age, and think this is potentially adding to my feelings as I try so hard to get the balance right of being present and advocating without taking over and allowing my feelings to cloud anything

I do not think you are being unreasonable at all. I know my kids have pet names and they get upset if it’s used on others. It matters as it’s significant to your child so for those with no experience of this and how the little things do really matter. Ignore the people who are dismissive of this.

Haven't read the full thread but YABVVVVU.

I have an ex-friend who had band anxiety diagnosed when she was 13/14. Her mum bent to everything, she left her dad because her dad refused to, and now my friend is 26 and cannot go anywhere without her mum. She can't even walk to the shop alone. Her mum has to drive her to work because she's incapable of functioning.

You need to deal with the feelings of worthlessness and help strengthen her mental resolve as opposed to just changing everything to make her feel comfortable.

If it wasn't this it would be something else are people supposed to walk on eggshells for her even though she would still find something to get upset over anyway , the world won't bend for your daughters mental health issues so she needs to learn to manage it and attend counselling etc

while that might sound harsh I do completely sympathise mental health issues are notoriously hard to deal with and reactions are usually completely ridiculous, irrational , over the top and un necessary for the situation .
I suffer with my mental health and often have to give my head a wobble because I know I'm being absolutely ridiculous but at the same time I recognise its my problem and others don't have to change things to appease me