Ok, so at the moment, you are already in arrears, and don't have the money to pay, so are hoping the Bank Holiday means they won't notice till you send the letter?
To be honest, it would be much better to have given a little notice, but it is done now.
You and your DH seem to have different ideas on what you can afford to pay. You are saying you can pay 2/3, so you would carry over 1/3 unpaid. Your DH is saying you can pay 1/6 and carry over 5/6. Why is that?
Realistically, you need to sit down, regardless of how rubbish you are with money, and work out what money you have until next pay day, what you need to pay out (including food, etc), and what is left.
Then you need to plan a budget for the other months, including the council tax bill. That must be pretty high, as we are near to the end of the tax year, and you have a court order for payment.
Then you need to work out how you got here, and why your DH didn't tell you that you were in difficulty, and why you didn't know yourself.
Once you have done all that (will take hours), you need to work out what you will tell your landlord.