Hariska, I will focus on emotions for both you and your daughter. Take whatever feels true to you, and leave the rest. I am not in anyway "an expert" in this area.
Your love and care for your daughter is wonderful. Often remind yourself that you made a smart choice and be confident that this will get better and better for your daughter, and family. Of course, when you see her struggling with studying you might have doubts about your choice - any parent would feel similarly. Let any doubt or concern be present, but choose to focus on any little improvement.
The more calm, patient, and confident you are able to be, that will support your daughter in learning what the new sounds mean. You have shown a lot of courage in joining this forum, asking for help. Know and let your daughter know that this group of people are smiling at her for her energy in practicing the audio exercises in rehabilitation, and for any little successes. Stitch-by-stich and after a while you have a beautiful scarf!
Any kind of learning is best supported by a relaxed and alert \& focused attention. Anxiety or frustration shouldn't be denied or pretend they aren't real, however focusing on those feelings makes them grow and undermines the better conditions for learning.
Some things you should let your daughter know and perhaps need to repeat often:
She has not done anything wrong. You love her just as she is right now.
The new and often strange sounds she is hearing are normal, and any kid would probably find some of them to be unpleasant or perhaps even scary, BUT this WILL change. She has the power to help it change.
It is OK to feel frustrated and annoyed with the sounds and all of the audio exercises; AND it is good to celebrate and enjoy each little bit of success, in fact helping her make a drawing or picture of each positive change would help. Decorate the walls of where she sleeps with some of these drawings and have them watch over her while she sleeps.
Find an explanation that would make sense to your daughter so that she has clear expectations of how things might change over the next weeks and months. If what she is told about how hearing might change and improve, AND then her own experience is somewhat similar to that it will support her in being more confident that the adventure she is on will have a happy ending.
There are many ways to make this into something of a "game" and to use her imagination. For example, the device that has been put in your ear(s) is a bit like having a very, very, very small rabbit that has come into our house and decided to live with our family, but it only wants to be with you. At first the rabbit is confused and a little scared because it is not used to living inside. Sometimes it complains and makes very odd sounds. Ask your daughter to learn to tame the rabbit and make it feel loved and comfortable. Perhaps have her give it a name (that she can keep secret, or share with you). Ask her what she is noticing about "the rabbit" and the sounds that it makes. What is it trying to tell her? What secrets does it have that it is gradually sharing with her? What magic powers does the rabbit have that it will give to her?
If your daughter is bilingual e.g. Nepali and English ... If you think it'd make sense to your daughter, you might use her learning and knowing those two languages; and are now learning another very, special foreign language.
It probably would also help your daughter to find how to tell her friends what is going on with her, and how they can help.
If possible, each day for yourself and your daughter find something that is beautiful, or something that makes you laugh. Balance some of the challenges in life right now with celebrating for just a minute some experience that makes you smile.
I am picturing each day and week getting easier and more enjoyable. Let us know what we can celebrate with you.