Illness affecting bond - should I separate?

My lil boy Mel is recovering from stasis. It's been 3 days since it started - took him to vet after first 12 hrs and have been giving him meds as well as syringe feeding. He began eating solid food (veg only) last night and passing little droppings.
I also have a larger, female bun - Tilly - who has been chucking things around and so on recently - probably spring fever. They have been bonded since November.

The problem is that since Mel became ill, Tilly isn't happy with him. The first day she snuggled up to him, but he would just walk off and hide somewhere. Now she seems annoyed, probably because he isn't grooming her.

I honestly thought Mel would die a couple of nights ago, so didn't put them away overnight in case he wanted to jump up and sleep on my bed (he does sometimes). I've also left doors open in my flat and he has been going into the other room but she hasn't (she usually does). This means they have basically been avoiding each other and sort of staking out their own bits of territory. Even in my bedroom - where their cage/run is - it's huge, so they have been avoiding each other. Tilly keeps chasing Mel.

Right now they're both in the cage/run, but Mel is keeping out of Tilly's way, otherwise he gets chased.

I'm concerned that this has affected their bond and not sure whether to let them roam and avoid each other for now. My main concern is that the stress will stop Mel getting better if I keep them close togther. In fact I'm half wondering if maybe something was wrong before and that's why he stopped eating...

If I do need to rebond I'll be looking for someone in NE England who can help as I don't know if I can cope with that again...
But I don't want to separate if not necessary.

Hmm judging by their behaviour, I think I've answered my own question here!
Poor Mel is hiding in the cage whilst Tilly guards the door... So have decided to let them out into the room for now. With another food bowl and possibly litter tray. Then they can avoid each other more comfortably...
I guess when Mel is completely better I will have to put them in a pen elsewhere, then neutralise the cage/run and put them back in it. Unless they decide to get on again in the meantime. I'm trying to groom them both when they are near each other. Mel is eating other food now, so that's good.

I hope they settle down together. Have you any ides what caused the stasis?

No idea what caused it. Which is making me wonder if it was Tilly's behaviour. Previously, she was lying across the door to the cage/run sometimes, as if to block Mel going in. But they were also lying happily together and not chasing when away at night so I ignored it.
It seems she has basically decided the cage/run is hers, and it seems to have started a bit before the stasis.
If I neutralise it and start again, will that work? Or will she take over again?
And is it related to spring fever, if so how long will it go on for?

ps. Mel eating noramlly again, have set aside a separate litter tray/water/food.