This stomach bug might end my marriage...

So I (31F) have been with my husband (35M) for 11 years. Most of that time has been great. We do almost everything together & I love him deeply.

The only place we're not 100% in sync is our sex drives. I've always been more interested in doing the deed than him, and have shared with him a lot of my kinks/desires. He's relatively vanilla in comparison, but would occasionally whisper things in my ear to get me going. The most common one is my wanting to watch him have sex with another woman. For most of our relationship, this "other woman" has been a nameless, faceless person, but recently we have both developed a crush on our mutual friend. And since that time his drive has skyrocketed. We've gone from once a fortnight to 4 times a week, and now the scenarios he talks about involve her specifically.

This has been great, until this week. I've had some kind of stomach flu. I've not been able to keep food down for days, had a fever, muscle aches and have been exploding out of both ends. I feel repulsive and absolutely disgusting... My husband claims he has no idea how to help, so I've been sending screenshots of google results for him to try.

At the same time, my husband has been taking our crush to work (she doesn't drive, and starts work at 4am) so she can save money on Ubers. He then comes home for an hour or so, before going to work himself (he starts at 6:30). He comes home, reminds me to shower, and then proceeds to go sit on the couch watching Facebook reels and YouTube. When he gets hungry, he orders food in (he's a great cook, just doesn't plan well). The house is filthy, there are empty cans everywhere, and the dishwasher hasn't been unstacked since I ran it on the weekend. This is the first time in days I've felt almost human, and so I've done a little tidying, but I don't want to do anything in the kitchen, because I'm not wanting to leave my germs everywhere...

I've just found out that my husband is going to our crush's place after work to body double with cleaning and then go to the laundry mat. Then they were going to come back over here and watch movies. She's going to sleep over, so he can drop her off at her sport event tomorrow.

I don't know what to do... I don't like people in my space at the best of times, which he knows, so this feels like an absolute betrayal. I'm trying to occupy as little space as possible, but I almost feel like I should be going somewhere else. I know I've not eaten in days so my judgement might be off, but I keep thinking about splitting our finances, and what the future would look like if we weren't together...

I'm not against Polyamory. And I know that our crush has been in a polyamorus relationship before. But I feel like I've been needing my husband, and he's just not been there for me...

UPDATE#1 I'm still not feeling great but I hope this makes sense.

My husband & I talked. He came home from work & did some chores. He ran a bath for me, got me drinks, and spent a good 5 hours in bed with me, stroking my back as we binged reels together. I was falling in & out of consciousness. He left maybe an hour ago (around 7.30pm), with my blessings, to go take her to the laundry mat. (I hope he took our sheets too... I'd really appreciate some clean bedding)

We have talked about being in a polyamorus relationships before. (He's got family members with multiple partners) Usually though, it's a matter of one of us dating someone else, rather than being a Thruple. But now we're talking about it in more serious terms. How living situations would go, how to split our finances, etc. I know it's silly, but we always agreed that our animals came first. We would rather eat nothing than instant ramen than forego their care.

As for our crush, she has just come out of a thruple (a long term couple. I suspect one partner only agreed to it to make the other happy). She's saying she wants time to herself to recover, as they really messed her up. So I don't think she'll be receptive to anything romantic for a while. In terms of personally, she's very intense. She has big goals and aspirations, and is working hard to meet them. HOWEVER, she's not great at doing self-preservation tasks (aka. eating, drinking water, showering)- hence why I send my husband over to make sure she's doing okay. I think she's adorable, and am excited to watch her succeed. She's also only ever gotten handsy with me, in a joking way, and often gets my husband involved in it too. (Aka. Me doing dangerous stuff, with no-one else home got me a smack on each cheek.)

Thanks to everyone who wished me to feel better. Honestly, I'm slowly starting to feel more human. Maybe I might make it to the couch later.