Your pregnancy is possibly retriggering your ED and you need to talk to professionals about that.
It can be a really risky time for people who have had ED, you said yourself in the opening post the feelings don't go away. You're showing early warning signs of a problem: you hate being pregnant, you hate your body changing, you're wondering if you look 'huge'.
You could be fine, you might not be. You need to tell your GP or midwife.
And to all those saying the DP is a prick or a cunt - presumably as they've been together for 15 years, he knows what living and loving someone with an ED is like.
And it's hard to balance what the right things to say are.
When someone with an ED asks 'how do I look/was I fast and you say 'yeah you look amazing/running, you were the best, so fast' can make someone think well then I clearly need to carry on with this running/food restriction since it's making me look great and be the best, in fact - if I do MORE, then i'll be even better/faster/look better.
Say 'it doesn't matter how you look/how fast you are, I think you're beautiful, the best, I love you no matter how you look or how fast or how pregnant you are' and that's easily interpreted by the ED mindset as 'well I must be f*ing huge and slow then if you say it doesn't matter and you love me anyway, that's what people say when someones ugly/fat'.
Sometimes a neutral answer seems best.