Son Has Disowned Me - Was I Wrong to Claim CM?

[ByUmberCrow]

Apologies - this is long.

Separated from abusive ex seven years ago. Left with our 3 DCs - DS1, DS2 and DD (12, 10 and 6 at the time)
One of the MANY reasons I left ex was because he was financially abusive - made me pay him the majority of my wages and child benefits, etc all went to him. He controlled everything financially and I had to justify everything tiny thing that I needed to buy or pay for.
Another reason is that ex pushed DS1 into an expensive - and very time consuming - hobby. Our lives were dictated by his practice & taking part in events.
About six months after I left, DS1 chose to live with his dad. The major reason DS1 returned to live with his dad is so that he would still be able to practice as much as before, even though their relationship was extremely fiery.
Ex has made the minimum possible effort to see DS2 and DD, and was extremely confrontational and aggressive when I approached him about even very minimal financial support, stating that it was my choice to leave and that he couldn’t afford to contribute, etc.
Not wanting to sour the relationship between him and the DCs, I left it alone and have worked tirelessly to support DS2 and DD as best I could. I also paid into DS1’s child trust fund regularly so that he had a lump sum of a few thousand pounds when he turned 18.
Recently, I have had to leave one of my two jobs so that I can be around more to support DD, who is struggling with anxiety, and with rising living costs, etc have begun to struggle to make ends meet.
Friends, family and school wellbeing contacts have all suggested that ex should be paying support, and I eventually submitted an application.
It seems that ex received the letter today, and I have received a message from DS1 stating that I am disgusting for doing so, and that he no longer wants anything to do with me.
I feel like I’ve done the wrong thing - have I?

Your oldest is not in a position to judge you. Ignore it.

No, of course you haven't.
Your ex has 3 children - he needs to pay his share for all of them.

Your Ds should not even be part of this discussion ..

Do expect counter claim from ex for older Ds ..

Your ex is in the wrong sadly it seems hard you will be able to protect him from this behaviour

Of course you aren't wrong!
Your ex is a terrible parent by involving your son in this.
I'd just say to your son 'I'm sorry to hear that you feel that way but this is an issue between your father and I. I hope one day you will understand but I won't be discussing this issue with you as it is not appropriate'
Take the high road. Your poor sin is being used by his dad essentially to try abd save him money, hoping your son will convince you to drop the claim.
But you are entitled to thar money.. he SHOULD be paying his fair share towards all of his children.

You aren't in the wrong.
DS1 is not in a position to make a valid judgement. He doesn't have all the facts. You can't make him.

You do have a responsibility to do your best for the 2 children who live with you. Carry on.

Ignore the little upstart!

I'd reply: 'This is between me and dad. I'm sorry he involved you. I won't be discussing it with you but want you to know I love you very much. Mum. X'

You have to wonder if the father has told the oldest that some sort of support he is getting is going to be cut off in order to pay for the maintenance. That would Be totally unfair, but could explain the son’s reaction.

Definitely don't send anything like that.

You’ve done nothing wrong.

Your son sounds like a chip off the old block where his father’s concerned.

Since DS1 is over 18 she won't be required to pay for him, but the youngest child has several years of still being a child and the father should definitely be paying for that.

Thanks all, I really appreciate you taking the time to reply.
I feel so sad, but in many ways unsurprised that this has happened - DS1 is definitely very similar to his dad in lots of ways.
I agree that it should be between ex and me, and that DS1 will not know all the facts - but ex is a classic narcissist and likes to announce to anyone who will listen how he has been ‘wronged’ and how nothing is ever his fault…

Update:
I haven’t responded to DS1 yet - and not sure that I will for the time being - but DS2 sent his brother a text (without my knowledge) telling him that he was out of order and that DS1 should apologise to me.
I’ve told DS2 not to get involved and that I didn’t want things to affect his and DDs relationship with their dad and brother.
I feel sad that it looks like this will cause fallout for them.
Ex and DS1 have no such qualms - they paid a visit to DS2 at his work on Sunday and each told him how badly this was going to affect them, how nasty and selfish I was and dragging up all sorts from the past.
DS2 held his own but I’m cross that he had to. Ex apparently offered for DS2 and I to go to his house so that ex could show us his income and outgoings and ‘prove’ that he couldn’t afford it. DS2 has had a few follow up texts since which he has ignored.
Received an email from ex this morning offering the same - the tone was very disdainful and ‘poor me’ on my ex’s part. I’ve not yet responded.
A part of me wants to contact CMS and withdraw the claim, but at the same time, feel like ex has dodged his financial responsibilities for more than long enough and don’t see why DS2 and DD shouldn’t be able to access opportunities that will help in their future, which is what I’d use the money for. I know times are tough, but they’re tough for everyone - and I’ve been doing it all alone, with two children to provide for.
Feeling really down.

Just ignore them or take up an air of bemused contempt “ Stop whining. your financial problems are your problem, not mine. I applied to get the money you owed me so either pay up or shut up.”

Make it so unpleasant for them to contact you that they stop. Bin their missives.