I don't run fenders for that reason. I wish I had a good or better answer than that. Fenders do help to keep the nasties off you but if they come loose the results are not good.
I hope you are not hurt. Bike looks to be damaged badly, lot of work to fix. You might be better off to replace and use the damaged bike for parts.
Norman

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norms-iron-works.tripod.com
motor assisted bicycle engine headlights that work off of your white power wire. check it out