Where to start....

[NotDoris]

I’ve been with my husband for 30 years, married for 20 and we have 2 children together. Things are not going well between us any more and I’m considering leaving him. I have enough savings to rent for a while, but I’m worried about my income and what benefits I might be able to claim as I currently only work between 18-22 hours a week at minimum wage.
I am totally at a loss of where to start in this, and heartbroken that I’m even considering this.

Well the benefits would be universal credit. You can see roughly how much here: www.entitledto.co.uk/
If kids are

Unfortunately working your hours is unlikely to yield many benefits, age of children is key - I will get nothing on an income of £1100 a month. Same time scales for me but it's him walking away and he says he'll pay up (note says he hasn't made any moves to actually separate beyond the spare room)

It's a huge decision to make. I am facing the same. All I would say is to ask yourself if you and your hubby have done everything to save your marriage if you want to remain married. It's tough I know. And if you are worried about finances it can be doubly hard. I have been advised to make a proper plan to leave, which it sounds like you are doing. Don't rush into making any decisions if you are not sure.
I will be thinking of you. Take care.

Thankyou x