You can organize a group of friends/relatives through Lotsa Helping Hands - you and maybe one other person could be the coordinators, and put up the tasks that would be helpful. For example, meals for the family 3 times a week, laundry, cleaning, carpools for any kids, whatever is needed. We've done it several times, with a cooler outside the garage or on the porch, and people drop off meals. LHH lets you post preferred meals or things to avoid, request disposable containers so nothing needs to be washed & returned, and so on.
She might like saltines, almonds, small cans of ginger ale, things easy on thes stomach. Also small bottles of hand lotion, small puzzle books (when she's too tired to do anything else), notes of encouragement, maybe a little book of inspirational sayings of encouragement. Nothing too long in case she doesn't have energy or focus, but something she can pick up and put down. Some women like a journal to record their thoughts and fears and hopes. Include 2 pens. If she's likely to lose her hair, then a couple of cute hats or scarfs or kerchiefs, whatever you think her style might be.
There have been clinical trials by oncologists using a particular company for nutritional supplements that help offset fatigue in cancer patients - safe for those with compromised immune system caused by chemo, easy to absorb to keep energy and nutrition up when faced with nausea, and so on. It's liquid so it's easy to digest (no pills), and it's all food, no drugs, so completely compatible with her treatment. The studies were conducted at 2 major cancer centers. If you think she'd like to know about that, let me know.