Reading buddhist texts leaves me feeling depressed?

Hello! I am new to buddhism and it’s something I’m fascinated by and trying to incorporate into my life. I am generally an optimistic person, it helps me to navigate day to day and gives me much hope to carry on living. Excessively so mayhaps but I find that when I am optimistic I am not often bothered by most things because I appreciate every little thing that comes in my way. I am also able to bounce back from negative events very quickly as well, I let go of emotions as temporary passages and I have innate belief that whatever life holds will be good in the future, especially when I do my best to treat others well etc. It makes me feel okay to be human and make mistakes.

With that being said, I’ve come into buddhism with the mind of being an apprentice, and I’ve found that it’s often left me feeling self critical and depressed, as if I’m not doing a good enough job of letting go yet or I’m acting like a fool and any optimism is short sighted etc. It also makes me more inclined to repress my feelings or not make mistakes out of fear of not being a good enough disciple who is calm and stoic. I can’t pin point where this feeling comes from and I understand that it may very well be irrational or baseless. My question is, can this optimism and buddhism coexist or fundamentally, must I abolish one for the other?

If I am misunderstanding buddhism please let me know. I am not afraid of being wrong and I understand there is much I have to learn. I want to understand if I am approaching this the wrong way or if there is something I can change from my end to be more receptive to Buddha’s teachings, because currently I am left feeling frustrated that it isn’t resonating with me when I believe in so many aspects of it.

Thank you, and have a good week.