Caught in a bit of downward spiral

I wouldn’t recommend brute force, mainly because there are just better methods and brute force is probably why you feel like you need to see a word multiple times for it to stick. Instead you can try to create your own mnemonics. WK’s are great, but if you can come up with something that sticks better for you specifically, that will be a huge plus. Also, depending on if you consume any content on the side, you can try incorporating sentences you’ve seen the word used in. Alternatively there’s the Anime Context Sentences script, that you can try. Also also, you can try learning how to write kanji, and then jot down the words/kanji you are currently studying, as that is also known to have helped quite a few people.
Brute force or rote memorization is probably the least efficient way you can go about it if you don’t yet have the neural pathways to make that easy.