AITA for considering ending my friendship?

Hello Friends I’ll start off by saying that i acknowledge that I am too nice. I (31F) have been friends with Scarlett (36F) for about 5 years. Scarlett has been in a very toxic relationship on and off for the last 7 years. During the course of this toxic relationship, she moved in with this person (who I’ll refer to as Matt) and also moved her mother in as well. Fast forward to this year, the relationship has turned tumultuous for the worst, and they worked towards a separation (there was a child involved and finance issues that prevented Scarlett & her mother from moving out). During this time, Scarlett began sleeping with Matt’s childhood best friend and eventually fell in love with him (i will refer to him as Justin). This was kept a secret from Matt as Scarlett needed a place to live.
This context is important to the grand scheme of things as I have supported Scarlett through this whole process. Beginning of December, Matt was adamant that Scarlett and her mother had to be out of his home (which it was his home, they were not on the lease) by mid December. Scarlett and her mother quickly did everything they could to try and secure an apartment, but could not by Matt’s deadline, and therefore had to move all of their things into a storage unit with nowhere to go. This is where my “being too nice” comes into play.
I offered them my couch for a few weeks until they could find a place. I was helping with rides to and from work as well as running errands. The part that really started to grind my gears is when Scarlett would leave her mom with me to go stay at Justin’s house; her reasoning being that they were “free” to do as they please now. I communicated that I would prefer she not leave me alone with her mom more often than not. The first week she was at Justin’s house 2 days then tells me that he is sick with flu symptoms; I asked her not to come back until he is well again as I cannot afford to get sick and miss work. She waits 1 day, then comes back sick herself, giving her mother and I both covid the weekend before Christmas. She took no accountability for this and still continued to go to work herself.
Fast forward to this week, her mother and I have been home extremely ill all week. Both of us have missed work. Scarlett takes off to Justin’s house without a word on Monday evening. Comes back Tuesday night just to go to work on Wednesday, and has now left me alone with her mother on Christmas to go back to Justin’s.
There’s bones I have to pick about her mother and the way she lives, but i’m trying not to nitpick at this point. But this is my home and i feel like I’m hiding in my bedroom to avoid her mother. They have secured a place and plan to move in this weekend, but I’m struggling because I value this friendship and it’s become clear (in my mind) that i’m not being valued the same way. I feel as though im being used as a place for her mother to go because she couldn’t bring her mom to Justin’s. I have continued to try to communicate my feelings but she just keeps saying “ she doesn’t understand how this is hurtful to me “. AITA for considering ending a several year friendship over this?