u/FirstAdvantage3266

Hi everyone, I need advice from the outside.
Little context, my husband (M30) and me (F27) have lived abroad for more than three years, meaning no extended family around, only us. Last year, we moved to my husband’s origin country (we are both from different countries) so only his family is here. I’m fine with this, we get along well.
Here comes the problem, my mother in law has a dog, a poodle, I like him but he can a pain in the a**, he is historical and temperamental.
A couple of days ago they had a trip and just assumed that we will take care of the dog. No questions asked. They just left him with us for 20 days. I have trouble slipping, and every little noise at night wakes me up. This dog (not his faults) is used to sleep on the bed with them. I didn’t allow this, even if I like him, the dog remains on the floor. This was also like this when I had my own dog, it was not going to change now. So we brought his things into the room and let him sleep on the floor inside the room, which I also didn’t wanted to do, but I thought okay, I’ll do the effort. Mind you, I didn’t sleep well for all of those days because the dog woke me up several time at night when he moved around or leaked his nose or whatever. Apart from that, he was sick and I had to clean his eyes twice a day and make sure that he took his medicine.
Finally this ended, and I thought this wouldn’t happened again. Spoiler, it did.
A couple of months passed and they told us, didn’t asked, that they are leaving the dog with us on 4 (FOUR) different weekends between June and July.
I don’t want to take care of him, I can’t sleep, and this even made me fight with my husband last time.
They only leave him with us because every other person they know has a dog. I don’t need to have a dog to say no. I don’t want to sacrifice my sleep and fighting with my husband because of this.
Can I say no? How? Am I the asswhole?