Why can't mě be used here
Because 'o' goes here with the locative, therefore mně.
'Mě' and 'mne' are genitive or accusative case and don't fit in this sentence.
Thank you for that. I am finding it a bit frustrating that no explanation is being given about the locative. It would be very helpful
Yes, I know. Maybe the useful summaries from http://cokdybysme.net/pdfs/ will help you, as long as further Tips and Notes are missing.
That's an amazing link, thank you.