This is definitely a hard time for her, and upsetting for you, as well.
Try to remember how very valuable you are for her,
to just listen, when you are able to, and to help out, in any ways.
There's no way you can make this easy for her, but it's much easier and better for her, with you in her life than not.
Don't feel useless, because believe me, you are not.
Just your caring about her, and doing some practical things to help, makes a world of difference, even though she will still be finding all of this, difficult.