Am I being stupid and potentially leaving myself in a vulnerable position?

I’m totally capable of loving someone without giving them money and assets.

If all the children between you two were yours together and your DP was just passive but not against the marriage, ideally you've discussed it before, your approach makes sense. Women don't have to wait for romantic proposal with a ring, sometimes agreeing to get married is absolutely ok

In this case the partner has children with someone else, never offered/promised marriage and very probably doesn't plan to get married - he supposwdly sees it them as a partnership of two adults with independent money.

Very probably, part of his refusal around the bathroom is, that he doesn't want the OP to invest in improvements of his home.

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So... while your case makes sense, the applicability on OP's situation is limited.

Sorry but he doesn't love you that much if he won't marry you or offer some security or make a will or change the bathroom.

I would want my home to go to my dc too.

It sounds like you’ve never really been on your own and that you have been conditioned to believe that you need a man to support you.

OP seems to only want this man for his money. She believes that marrying him would give her financial security because she would inherit his property or at least have some claim on it. If this was a man posting he would get pasted on here.

OP talks about the sunken cost fallacy as if she has committed herself to the extent that changing the situation would mean taking a financial hit. But she has not had any more costs than she would have done if she had remained in her own house for the last 5 years. In fact, she would have had a mortgage to pay on top of her utilities!

She's been living rent free and only paying her rightful share of the bills. The man could not have been more reasonable. On top of that she now wants him to fork out for home improvements which she wants and he doesn't.

OP if you are still reading, you know what you have to do. You need a job so that you can either secure a mortgage and buy a home of your own or use your wages to live off and protect the proceeds of the sale of your house. Your semi retirement has to come to an end because you can't actually afford early retirement.

Actually, it isn't his responsibility to make up for the previous financial abuse you suffered . It's your responsibility to look out for yourself , and since you rightly feel nervous about the current situation and can't reach an agreement you are both happy with , you need to take independent action.
Maybe buy a flat and live separately, maybe buy a small rental property, maybe invest tge money so it's available to pay a future deposit. It doesn't matter if he's upset by your choice. In order to feel safe you need to trust yourself, not someone else.

What is not reasonable is him trying to prevent her from buying a property of her own, through his emotional reaction when she mentioned this to him.

It's not really to do with her buying a property of her own, she told him she would buy a property to live in, which is what he got upset about because he sees that as them breaking up.

If she was serious abut them getting married, moving out would be the last thing on her mind, she would be looking at buying a house and renting it out so she has always got that asset herself, but she is not interested in securing her OWN financial security. She wants him to hand his over to her, and is using threats of moving out to get her own way.

He is providing a property for you to live in rent free ehilst you sit on the profits of your house sale. I would say you are on to a pretty good thing there!

Fair enough but he hasnt actually done that
Has he?
Hes emotionally unavailable and shouts at her if she asks if they can fix the bathroom
Her money is dripping away, he is emotionally abusing and blackmailing Op into not buying herself a property
Hes NOT a loving partner

You need to prioritise your financial security. If get upset then he needs to commit to making changes to give you that security.

She can't afford a mortgage now, let alone in the future, so using 'moving out into her own place' as a bargaining chip to force him to give her financial security is just an empty threat to get him to comply, and says a lot about what OP is prepared to do to get her own way.

He doesn't want to lose her, so has said he would be upset if she moved out, which is understandable, but why should he get married or sign over half his assets to keep her from moving out?? Ultimatums never really work the way people want them to for good reason sometimes.

She needed to have bought her own place and rented it out if she wanted a guaranteed roof over her head for life, or used her money more wisely, though about her job in more practical terms, she has had 5 years living rent free to built a financial support system for herself, but hasn't bothered, instead she's pinned all her hopes on him handing over everything he's worked for.

In a nutshell:
He wants to safeguard his financial assets (fair enough)
He doesn't want you to invest in a financial asset to safeguard yourself.

To me, that's a deal-breaker. Summon up your independence and TELL him that's what you're going to do. If he still won't engage with anything you're telling him is important to you, you'll leave. Your life will be unimaginably better. Starting again can be wonderful. Right now, you're miserable and have no security in your relationship or financial status. The alternative to that is starting again on your own in a home that isn't mouldy. There is no option where you stay with him and be happy. Sorry to be blunt but I can see you know how desperately wrong this situation is for you.

You can't get married when only one person wants to!

Her partner has been absolutely clear he does not want to. And he has very good grounds not to get married. That is a reasonable view he has.

What is not reasonable is him trying to prevent her from buying a property of her own, through his emotional reaction when she mentioned this to him.

I’d buy a property and rent it out just so you have your own place if he leaves you or dies.

Pretty sure no lodger would put up with a mouldy bathroom! He's sees you as less than even that.

A RIO mortgage requires interest only payments. It's ideal for someone who doesn't have kids and therefore doesn't feel like they have to leave anything to anyone. They're targeted at people who only have a pension/pensions and/or unreliable income, so long as they have a deposit and are over 50. Interest rates are high - 6% ish - but it's not true to say it's harder to get a mortgage as one gets older.

Because she would have nowhere to live and the closer and closer she gets to retirement the harder and harder it will be to get a mortgage. Nevermind the difficulty of paying a mortgage out of a pension.

She is dithering and dallying and living in a gross environment instead of rectifying that situation now.

She's been living rent free for five years and has nothing to show for it? Who's fault is that?

Which doesn’t detract from what I wrote, right? She’s leaving herself incredibly vulnerable and needs to rectify that now.

Are you helping with childcare?

You are leaving yourself incredibly vulnerable if this relationship ends / he dies.

Why is she? In reality she should be no worse off than when she started.. she chose to sell her house, she chose to work an unstable job and eat into all her savings. His house isn't hers to 'claim' and never will be, good for him.

She's been living rent free for five years and has nothing to show for it? Who's fault is that?

How is he 'using the arse off' her?
She is living in his house, that he paid for, rent-free for the last five years. If anything, she's using him.
I have sympathy for the OP but I think on some level she saw moving in with him as a way to escape the job she hated.
If she was a man everyone would be calling her a cocklodger.
The partner is far from perfect but he is an irrelevance here. The reality is that she is responsible for securing her own future, no one else.

She doesn’t have it good in so far as she has nowhere to live in old age if this relationship goes tits up and when she suggested doing something about that (buying herself a property) he “got upset”. She just needs to do that and not worry about his reaction.

Assuming those 2 things are not related?

AND you already had 2 dc WITH him?

Anybody can declare love. But it’s a verb and he is not doing much to demonstrate it

The fact you have to delicately and “gently” ask him basic things is a red flag in itself. You are leaving yourself incredibly vulnerable if this relationship ends / he dies. You need to prioritise your financial security. If get upset then he needs to commit to making changes to give you that security. Although I would likely be put off this man full stop. The bathroom alone and everything being on his terms. Whose idea was it to move in so quickly.

In your post you state you don’t want to be financially vulnerable following your experience with a previous split. This is sensible and applies to both of you.

Living with him means you don’t pay rent or a mortgage. Which is a significant outgoing for most people. Further being able to split other living costs is less expensive than living on your own. By moving in with him you should have more disposable income.

When you sold, you released equity and this is yours to invest or save as you see fit. What you invest in is up to you. I wouldn’t buy a BTL without establishing if this will give you a better yield than other options. This is not the case for a lot of property investment atm.

By moving in with him you have been able to reduce your outgoings and invest your capital and additional income as you see fit. As you say it is important you don’t put that at risk but this principle applies to him.

Yeah but it sounds like HE doesn't want to get married. And at that point, one 'no' means there's no way forward.

OP needs to leave; he doesn't want to marry her.