Opinions/advice needed

Hey guys.

New to the forum and this is my first time posting here. Im looking for some advice/opinions on abit of a difficult situation.

For context heres some background.
I have a 12 year old son with my ex and a 2 year old son with my current partner.

Split from my ex around 6-7 years ago, she had an affair and left. Things have not been amicable and shes made my life [censored], including false allegations of domestic abuse and coersive control. She has BPD and is very narcessistic.

I had 50/50 care until 2022, my ex wanted to move to a different part of the country (5 hours drive) but my son didnt want to move so we went through court and got a child arrangements order for my son to live with me and spend half of the school holidays at his mums new house throughout the year.
<span;>Last summer we went through court again because he decided he wanted to go and live with his mum instead so now the child arrangements order is reversed and he has half school holidays to me throughout the year, although this only totals approx 6 weeks out of 52 weeks.

I have a good relationship with my son and i love him dearly. Ive always been consistent and present in his life, ive tried to set a good example and teach him how to be a good person. My partner also loves him like her own and is an incredible stepmother to him.

My prediciment is that i have been offered an amazing oppurtunity to go and work in australia on a sponsership visa with my current partner and our 2 year old son and then gain permenant residency after approx 2.5 years. She is 100% behind the idea of us going and has said she would ideally want my eldest to join us, but understands that probably would be impossible due to my ex (i understand she wouldnt want him to move, i wouldnt either so im not holding any grudges against her for that). I would earn good money due to my skills being in high demand in Australia and whilst there will always be cons to moving, it seems like the pros outweigh them and the quality of life/once in a lifetime experience/further career potential for both me and my partner would be something we might regret if we didn't do it, let's face it, the UK is a shambles. It would also open up opportunities to my eldest son to visit Australia every year and when he's 16 if he wanted to move there aswel, it would be a simple process.

I don't know if my eldest son would want to relocate with me now but even if he did there is absolutely no chance my ex would allow him to move with me so him coming with us would be a straight no.

So my choices are relocate without him, explain that i am not abandoning him or anything like that, keep regular indirect contact through facetime and messages, plus with careful planning he could come and visit every summer for the entire 6 week holidays. It would ultimately be a case of pretty much the same quantity of time but rather than spread through the year, it would be altogether during the school summer holidays. Same quantity more quality.

Or turn down the job offer and stay in the UK.

The thought of leaving him absolutely breaks my heart and I've cried many times at the thought of him being left behind whilst I jet off for a "new life abroad". I hate that he might think I'm abandoning him and I have absolutely no doubt that my ex would push that narrative so I would really need to be persistent in explaining that's not the case.

But I also feel that if i turn down the job, it's not fair for my youngest son and partner to miss out on an amazing opportunity at a better quality of life in a beautiful country.

Im stuck between a rock and a hard place. If it wasn't for my eldest son being left behind I'd be on the plane now.

Has anyone else ever been in a similar situation,  or known of anybody who has?
Did you or somebody else go through with it or not?
And either way was there any regret?

I have been told that I need to give an answer very soon. If I accept the job then I could potentially be moving in 6 months depending on the visa application, which ive been told will be quite straightforward due to me and my partner having no criminal history and also my qualifications being in demand. However once the process starts I'm committed, the company is investing alot of money into getting me there by paying the sponsorship fees/visa fees/plane tickets and if I start the process then pull out, I'm liable to repay that money to them, which could be around £10,000.

Does anyone have any opinions or advice please?
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