You need to decide if you want to get married or not. If it's not a big deal to you, then tell him to stop fiddling around with these empty promises, that you are confident in the permanence of your relationship without a ring etc. but you need to sort some paperwork out regarding your position re. the house etc. Then get onto that by the end of this week.
If you DO want to get married, and do not wish to stay together otherwise, then you need to accept that he does NOT want to get married to you, but has been manipulating you for years, and you are looking at breaking up at some point in the near future. This is not the end of the world, but it is very alarming that you don't have sufficient access to funds to book a registry office ceremony (less than £100) - you need to sort that out right away by going back to work.
Whatever you decide, you need to get some financial independence. You cannot be a SAHM for somebody who is not married to you. You are giving up your earning power AND you have no rights to his property or money, which remains HIS property & money because he is not married to anybody. You are extremely vulnerable, esp. if he is now giving you the silent treatment because you questioned him last night.
Incidentally, if he does agree to get engaged (and what does he think that means? you've been engaged for years already!), a) he is going to push to set a date in 2018 or something, and b) he is going to hold over you indefinitely the idea that you "forced" him into it.