Hi Foolingmyself.
I have a similar story.
My udd left her 2 small children with me for an overnight stay and didnt turn up again until 2 wks later. She turned her phone off moments after she left my home and hadnt left details with anyone about where she had gone, even the gc daycare dint know anything, so I made a missing persons police report, but they coudnt find her.
Turns out that she had gone to spend time with the new "love of her life" and said it was all down to miss communication on my part and that I was overeacting. Extended family actually believed her and belived that I was blowing it out of all porportion. Easy to say and very invalidating at the time as they only seemed to want to hear udd's side.
Opinions of many of these family members have since changed as a quite a few who took her in asked her to leave shortly afterwards because of her behaviour. Unless your relative has zero rules in her home I cant see how long she will be there especially if she is making plans as to live life as a single woman for the summer with this new man. I also think it is important to try stay on good terms with this relative for gc's sake if udd decides to suddenly take off with him.
I can imagine how overwhelmed you feel but as you say you are exhausted. we all have our limits. Just know that you have done your best and it is time to put yourself first.
