Feeling like a fraud when I do well, maybe due to my apathy about academia?

This is what is known as 'imposter syndrome', a psychological problem which is typically accompanied by an individual doubting their abilities/talents, while persistently trying to internalised themself as a fraud. The reason your classmates are jealous of your success is because you're better than them, and possibly have an incredible amount of knowledge. The issue with imposter syndrome is that these people can have a wealth of knowledge but feel that they do not

Thank you for your quick reply. I genuinely feel like I don't know a lot, though. I often forget basic information (especially when nervous), and I am someone who is quite strategic at studying for exams, too, so I feel like my knowledge isn't as deep? But I guess I've never considered having imposter syndrome before, and it does sound like what I've been feeling.

Are you good at your specific niche and have general knowledge of some other areas in your field? Many other people are the same, and I would think this is normal. A lot of journals are written by a group of experts with specialised knowledge, and they tend to work together because not one person can know everything.

I don't even feel like I'm good at my specific niche, but I did extremely well in my thesis so I must be doing something right. I'm hoping to spend this year building my general knowledge of other areas, but you're right, I guess I don't need to know absolutely everything.

This graph might help (linked below). The important content to know is the stuff which is relevant, and it seems you succeeded in this case if you excelled in your thesis. Sounds good about the building your general knowledge of other areas, are these areas in the same or another discipline?

https://www.google.com/imgres?imgurl=https://images.squarespace-cdn.com/content/v1/5a8ec7a44c0dbfc5c297f8d1/1558453055924-N88Z2BWEN3THSX03GH5Y/ke17ZwdGBToddI8pDm48kG4VqDreF-qTqyP-RyQBlzwUqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcz9FKOkYZZtCaZTQFz_pq4njr3fQnFjhxZuT9qSS4BtKI42iWDYN3Yj3ILGKtJgbC/Add%2Ba%2Bheading%2B%25281%2529.png&imgrefurl=https://getwerkin.com/blog/imposter-syndrome&tbnid=Es_OSljtM5G2-M&vet=1&docid=MYM69Uik3DGe4M&w=1000&h=500&source=sh/x/im

Gosh, that graph is really interesting. I relate to that a lot. Thank you.

The areas I need to build are more contextual around my main area of study, but do overlap a little, which is always nice yet refreshing.