My heart is aching for you, and for your beautiful children who may not know the details, but who will be very aware of the dreadful atmosphere and unhappiness in the house.
I can understand your being paralysed - over the years you have got into a mindset that this is all that life has for yo, and horrible as it is, it is familiarandyou know where you are with it. Stepping into the unknown - eve when that unknown promises so much more - is terrifying and very difficult.
If you can't do it for yourself, do it for your children. Don't let them grow up thinking that this is what a relationship is like. Don't teach your sons to be abusive and your daughters to accept it. They, and you, are worth so much more.
If you fear him emptying the house, have the locks changed (explain to the landlord - s/he may do it for you if you reimburse them, then your partner has no comeback on you. MAKE SURE HE DOES NOT GET HOLD OF A KEY. (Explain that you are the one who pays the rent, and if you move out he won't be able to and will have to be forcibly evicted. LLs don't like having to go down that route s it is expensive and time-consuming).
And if he does empty the house (where would he go with the stuff - he has nowhere to store it?) then let him! Look on Freecycle, ask friends (you would be amazed at what people throw out that is in very good condition), go to charity shops - heck, I'll bet that there are MNers in your area who would come up with the goods to fill a house from eaves to foundations if they got the chance.
Are you both the lease (that would complicate things a bit)? Have a word with the Citizens' Advice.
He is emotionally abusive, to you and your children (even he doesn't bully them, they are affected by the way he treats you, and he s manipulative towards them.)
Please get out now - you are still young, you still have your health - but won't for logic you allow this to continue.
I'm holding you in my heart.