Clingy Preschooler.

It all got worse about 6 weeks ago when my mom had surgery and stayed in the hospital for a week. My mom had a bilateral mastectomy.
But I figured that LO would be better by now. I understand her not knowing exactly what is going on and such but it has been 5 weeks since my mom has been out of the hospital.
I am honestly concerned. If she isn't right on my hip or sitting next to me at the dinner table or on the couch she is watching a show which will keep her distracted enough for me to get something done. She was sleeping in her bed all night before this and now wakes up screaming 2-3 times a night and ends up in my bed.
She knows that grandma is going to be sick soon( Chemo), and has surgery again. I just thought it would get better once she knew that grandma was ok.

What do I do about this? Just give her the attention she needs, but how long is too long for a 3 year old to act like this?
The minute we get into her classroom or her daycare she wants her teacher or daycare provider to hold her. She is right by their side just like she is right by mine.
I am going crazy with her being this clingy.