Hello there.
Her behavioural problems being quite aggressive and growling could be partly due to hormones and partly being confined to her cage (you don’t mention if she has any time to come out and run around every day). Female buns in particular if not spayed can have a tendency to be quite defensive of their cage space, her cage is her home and safe space and she considers you an intruder. You can help her out by letting her out to run around before reaching in to clean out her litter tray or change her food etc. If you do have to reach into her cage while she is in there, talk softly to her and move slowly in a very non threatening way. Spaying would likely help greatly with this behaviour as it can be quite hormone driven and given you have only had her 2 months I imagine she was young when you got her so she will now be likely entering puberty which is why you are seeing the sudden behavioural change.
The excessive grooming is concerning. This could be a result of boredom if she doesn’t get play time, but it could also be a result of illness. Mites, or a fungal infection are common causes of hair loss in rabbits, both should be seen by a vet. Some vets do payment plans so I think that will be a good idea of something you should look into, ring around near you and find a place that offers it or something similar. Bun does need to see a vet so however you work it out.
In regards to her diet, you really need to get her eating hay, it’s the most important part of their diet not only for their gut health but for their dental health too. Pellets don’t wear down teeth like chewing hay does and overgrown teeth can be very expensive. Try different types of hay, different brands, different grasses, if you contact some companies online you may be able to get them to send you samples so that you can find something that your bun likes before buying something that will go to waste. You could also start by trying out something like the oxbow harvest stacks, or another brand of compressed hay block. They’re not ideal but they can sometimes tempt buns who are used to eating only pellets into starting to eat hay, and compressed hay blocks are better than no hay at all. How many pellets are you feeding a day? In terms of a measurement like a cup measure? Does she have access to them at all times or do you have set meal times? It’s important for buns not to go hungry, but she does need to feel hungry before she is likely to try something new. So if she has access to pellets all day whenever she likes I would make set meal times for her. Serving about 3 times a day that last her almost until her next meal. Then at the next meal you can offer something like the hay stacks or hay first and leave that in with her for an hour to see if she’ll eat them, if she continually refuses you’ll have to give her pellets as a bun not eating can become a serious health issue very quickly. But there is a balance between letting her go a little bit hungry so that she eats what’s in front of her vs leaving it too long.
I hope I’ve been some help. Hopefully some more people can chime in with other ideas regarding the hay