gemmummy I am forces and have been through this although didn't have DC with my Ex so harder for you.
I take it by the fact you may be going to Cyprus that you are light blue.
The additional childcare there is very good and it is easy to get a good on island au pair -one of my friends went there and coped well whilst her DH was deployed.
You need to contact Family Services for help and support, they will allocate you a worker who will help you through all of this. They will ensure he gets out of the house -today if necessary.
You also need to report it to your boss, and tell your ExH you are reporting it . It is a breach of the social code especially if she is also serving. If she is in his Chain of Command then his boss needs to know as well as they must be interviewed and potentially moved at work.
Speak to your line manager and explain that due to the exceptional circumstances you may need to change your shifts to accomodate childcare in the short term. The additional stress of this may impact your work therfore if you tell your boss you shold get support and it won't end up affecting your annual report if you are not as efficient as usual.
Again speak to Family Services/Welfare and they can help facilitate this.
As said get to the STD clinic, not nice but better to check now and get it over and done with.
Get all your finances separated as quickly as you can, it makes the whole dealing with the ex easier as there is one less thing to need to discuss.
Get on entitled to. com Just because you are in the armed forces does not mean you are not entitled to working tax credit and child tax credit - take a look the extra money may help with extra childcare costs.
Depending on the size of your quarter you may be entitled to a larger one if you get a live in nannny or au pair, it is the regulations that you are so if you decide to go down that route push for it -again get family services on your side and get them to help with the process.
PM if you need any advice.