Am I overreacting

[Lyra25]

My partner and I had an agreement about our property as to the percentages of equity. For context, I hold more.
we agreed that this would be resigned post marriage to confirm the previous agreement re split still is intended to stand.
I mentioned it a couple of weeks ago and the reply was ‘oh I don’t think those things matter’. I didn’t push it further and mentioned it again at the weekend. The reply that time was you’d be worse off (as he’s since put money in). This is not true as it still amounts to around 90/10 split in my favour and there is mechanism in the original deed to deal with this anyway.
I was upset about this as I felt it was evasive and trying to side step the agreement to re sign it.
he says I’ve interpreted what he said incorrectly but hasn’t provided and alternative meaning other than to say he didn’t say he wouldn’t sign it.
I’m upset on two fronts, firstly the trying to avoid the original agreement but perhaps more so, for trying to deny what he said or what it meant.
AIBU

What was legally agreed and documented
that’s all that’ll matter

If you stay married for a reasonable amount of time, which I presume is the expectation! Won't it be split 50/50 regardless? I know different regions have different rules on this, where are you?

With that attitude off him I’d officially register separation now to make sure your % of property is kept safe!

I would expect it would mean he's 100% committed to the relationship, thinks you are too so it's completely irrelevant.
Like most people don't want prenups, because they don't want to go into marriage thinking it might fail, and think that if you aren't committed, what is the point?

No that’s not always the case. It depends on whether there’s enough money to meet both parties’ needs, beyond that there may be consideration of who brought what into the marriage. That said, say for example he met someone else and got them pregnant I would t want that to mean he got some of my pre marriage assets. So would want some protection for those

Do you have children from a previous relationship OP? For me that would be the main reason for this kind of agreement.

Yes exactly this

Have you now married him? Or is this still a discussion ahead of the wedding?

Ahead of

Why do you want to marry him? If your already squabbling about who has what equity, confusing matters further and putting yourself at risk of losing some of your assets in divorce seems stupid.

OP it's late and I'm tired so apologies but, do you mean resigned as in quitting the arrangement, or do you mean re-signed, as in firming it up? Is this a legal agreement like a pre-nup, are they even enforceable?

If you mean to firm it up, and he's trying to wriggle out of it altogether now, then don't marry him. Protect your asset and your kids inheritance. He's probably thinking "what's yours is mine" but if you're not both on the same page then I'd say that sound you hear is alarm bells.

Sorry, I meant re-sign rather than resign!

& yes it is a legal agreement. The enforceability is questionable, though I understand that weight will be given to it, I don’t think that you can fully restrict the court’s ability to redistribute assets on divorce. But it is taken into consideration.

If you have kids that aren’t his then by marrying him you are risking your DC’s inheritance should you die.

Have you considered putting your portion of the home into a trust for your DC? You would need specialist advice on to how best to set that up, but it could also protect you ( I think) from losing assets in a divorce.