Advice regarding losing feelings, long read

Been with my GF for 2 years; Her mental health has improved so much because I'm very stable and non-tempremental. No drinking, clubbing and basically 0 problems so she has had a very safe space to heal and work on herself. My bare minimum is sending her around, thinking of her when shopping, asking after her & her mental health, complimenting her, talking about her interests and being a decent human being in general.

But she's never really been the type to say "thank you for (something specifically)" or "I'm at Krispy Kreme, do you want a donut?". The best way I can describe it is she's hyper-practical, e.g. there's a movie I really want to watch with her but she's not interested so she won't watch it with me because it's a waste of my money to her. Or I want to bring her to my favourite KBBQ joint but she isn't a huge fan of meat so she wouldn't want to waste my money there. But from my POV, it's the small sacrifices & compromises that mean a lot to me - it felt like I've been making sacrifices doing things I don't feel like doing but I should do (as a man, like driving out 30minutes to meet her for dinner after a tiring day at work instead of asking to meet in the middle). More importantly, it feels like my friends give me more validation & recognition than her (e.g. complimenting my new tattoo whereas she's just "...eh its alright" or telling me they're proud of me and the efforts im putting into my studies etc). To her, she said she doesn't want to give empty compliments if she really thinks the tattoo is alright, my daily fits are alright and so on. Even though she knows I'm big on tattoos and fashion.

The crux of the issue is that I've been holding onto the resentment or bitterness ("i can make these sacrifices for her to make her happy, why can't she make some for me too? it should be a give & take but it feels like i'm giving and giving without ever taking") for almost a year and I've been so so unhappy feeling unappreciated in the relationship. Problem is half of it is a misunderstanding on both our thought processes, and half of it is that I didn't have the courage to bring it up properly and instead brought it up casually as "can you compliment me more" or "can our next few dates be something i want to do instead". She does change for a week or two, then it tapers down again. It's really not natural for her.

We recently had a serious talk recently on the verge of breaking up, because I had mentally checked out & mentally broken up already. The feeling of being unloved and unrecognised for over a year was unbearable. But she said to give us a chance again and she resolved herself to change. She has really put in a ton of effort too and I see it.

We are giving it another 2-3 months to see how it goes as we've been together for 2 years already

Help me resolve some questions:

1. I'm so afraid that I simply cannot untangle the bitter knot in my heart that's been festering for so long. It's basically a scar, and it feels like the love has withered. Am I the asshole if I genuinely can't get over this feeling and decide to break it off after 3 months even after she's grown into a better partner for me after a ton of effort?

2. She is genuinely giving her 100% in her own capacity everyday to fight her mental health battles and be a good GF. But what if it simply isn't enough for me & I feel it's unfair for me to have to give 150% to make her safe and happy despite feeling so unrecognised for the past year - thats probably the best way I can put it where no one is truly wrong and that's what makes it so hard

3. She is and will change into a better partner for me, but I'm afraid I'll feel like I "owe" her the relationship after 3 months at this point. But isn't that stringing her along, and isn't that a scummy thing to do as well?

4. Digging deep deep down, the festering wound really was the constant thought of "wouldnt i be happier and more appreciated with someone else", "im so unhappy being unrecognised in the relationship" and "i really would be happier out of this relationship and i just want to be happy" over many months. If anyone's had these thoughts before, is it possible to reverse these thoughts and truly love her again? I genuinely feel like these thoughts are extremely hard to somehow change my mind on as it's like a deeply cut scar. Am I the asshole for thinking this?