I got way too bogged down in character feelings. Never fixed it, just found a genre it fit better in. When writing psychological and horror stuff constantly being in a characters head works a lot more than action adventure. My flowery, wordy prose bogged down the pacing because I was trying to write a fast pace story, instead of taking a step back and seeing "hmm. Prose I snapped up from all those gothic horror classics is probably better suited for something more akin to said gothic horror classics..". Trying to juggle a huge cast, while getting stuck in their heads, instead of realising my work is much more suited for watching one or two characters break apart at the seams.
So I guess my mistake was just having the wrong writing style for the genre. I'm not entirely sure how much sense that all makes. But I suppose if your plot is straying, look at what it more strays towards and see if that's what you need to start writing instead.