Any battery that has to sit for extended periods will fail faster than a battery used every day. Who has ever had a garden tractor that had the battery die from winter storage? A brand new one will be dead in spring. I mean we learn and put a trickle charger on it. I am sure there is no exclusive parasitic draw on my garden tractor but this happens. It happens to truck batteries too, especially weak ones. I have no idea how old OP's battery, but it is time for a new one and if your gonna park for extended periods, get a battery tender and connect the battery portion to something that doesn't move and direct it near the wheel well so that you can connect it easily. This may or may not be feasible. I run an extension cord to get the distance and put the charger in a big open zip lock on top of the tire to keep it out of the elements. I trickle charge mine cause it sits for extended periods too. Cold weather will really help discharge it so consider trying this in the future if it's dooable. I trickle charge everything with a battery around here. My tractor has a 6 year old battery and still running strong. It's a 3 year battery. That is what is printed on it anyway. The little bit of extra work pays off. These chargers work well and are small and cheap. Like $25 for one of them. My ATV needs one cause it sits a lot. Try it if you can. You will have batteries last a great amount of time. This guy has a real easy connection lol.