Yes Grimchas, it's the underlying belief part that's so depressing, & scary, & such a giant red flag.
No doubt he was a wonderful b/f in many ways as OP gave him 6 years & believed he was made of the right stuff to sgare a child with - & why wouldn't she, given all he told her (but either didn't mean or is lying about now).
But he's not partner material, & now OP knows this about his core belief structure, his willingness to use her body as a fertility test dummy (or lie that he is - proof of mindset either way) & his basic cruelty in putting his feelings so highly above hers ... breathtaking.
OP - playing your cards close to your chest is great advice.
Apologies as the next bit is going to be cold & calculating. I'm a bit horrified at myself for even thinking it, but needs must & I'm concerned about your dependence on this man's roof.
Right now, having given up your old place to move into his, you are vulnerable. DP holds the most cards as he must be aware that you don't have access to the kind of funds that could get you a new rental tomorrow.
However - all the while you are pregnant & have not yet made your decision - you hold the single most powerful card.
Depending on how this sits with you morally, given his appalling turnaround, & treatment of your body & choices as his disposable toys, you might want to consider the leverage you currently have.
Does HE have savings?
Because, depending on what you want, you could present a case to him to exchange cash for termination. I know how that sounds. I know how disgusting the entire premise is. I understand the nature of precedent & the appalling way the concept could be leveraged by any Roe vs: Wade denier who doesn't give a shit about women's rights. But he has put you in an extremely tight spot.
And ... this is the sneaky part, but a liar doesn't deserve honesty from you when you are at such an immense crossroad of his making ... who's to say, once you have the cash, that you have to go through with a termination?
My guess is that he wants you to terminate, & continue the cohabiting relationship as if nothing's changed. If YOU pretend to want that too, there is your ONE opportunity to play the card game of your life, & walk away with enough £££ to start again, & make your own decision about the pregnancy separate to that.
How you would present it depends on what you think he will go along with. I would be tempted to broach something along the lines of needing a break to deal with the hurt & think about the relationship while you organise the medical side. Tell him you want a few days at a hotel while you investigate private clinics, & that he's paying, as it's the least he can do after doing such damage to the relationship.
Take the cash, save it by staying with a friend, organise a (free) medically induced termination IF you still want one, & spend the time away from him on rightmove & chatting up rental agents.
Humble apologies if the suggestion is morally repugnant to you OP.
But I don't think an honest request for him to pay you to move out would land in your favour. He's shown how much he cares about you & what you want. He's possibly only prepared to fund what HE wants, & I suspect he wants you to keep living with him as if this shitstorm is just a minor blip.