Mouse and Keyboard Question

[Scion Dracos]

Thus far my experience with RDR2 seems to be the journey toward finding a control scheme that doesn't make me want to tear my hair out. 

I'm playing 1st person and switched from a controller (which was a good old clusterf*ck of contextual controls and cameras trying to auto-center at absurd times while often failing to do so when I needed it to) to a mouse and keyboard and so far so good... with one caveat. I cannot control my horse's speed. I've tried both options: normal and tap and hold. Neither work. The tap and hold looks like it should but if I tap A or D to adjust direction all of a sudden the horse is speeding up. I don't know, maybe the way the keyboard talks to the computer confuses it or something. Either way I'm soon in a gallop or watching my horse try to overtake the NPC I'm supposed to be following. 

Is there something I can do? Or is this just a game I'm going to have to forget about completing due to a complete inability to find a control scheme that doesn't drive me crazy? 

Apologies for the tone. My frustration may be getting the better of me. 

Cheers

Edited December 29, 2019 by Scion Dracos