I don't think "professional help" will be any good for her. She can improve at her own pace with Rihito's support. She's got the most important thing you need for self improvement; motivation
While I agree with the sentiment of her not needing professional help, I can't completely attribute to motivation in this case.
I'd more so attribute it to the healthier environment and outlet her friendship with Rihito gives her. It lets her do things at her pace while keeping her grounded in not doing things too far in either way. Any slip up can be mitigated and there is no pressure on her.
Your comment about motivation was a real knife in the chest for me, since I have been having motivation problems (in the context of improvement) for over the past two years and have had moments where sheer motivation wasn't enough. I've been fortunate enough for getting off easy from my mishaps and being able get through life, but the right way to go about it is probably actually addressing the issue.
This comment was partly to contextualise things for myself, and I was going to the mention how motivation is the wrong way to handle things based off of the 'if I had a partner I'd have the motivation to get better' sentiment I see from time to time, but now I see how her and my situations' don't really perfectly apply to one another. I was mostly set off by the buzzword of motivation. The conclusion could be to motivate yourself on behalf of another person, but that just shows again that the two situations don't overlap (
cough cough improving myself to get on better terms with somebody is not something I can apply to help my situation), which makes me feel silly trying to connect the situation, merely at the mention of the word 'motivation'.
(I'm in general fine if it didn't seem that way)