I think you need to step back and really ask yourself what is going on.
You work in a corp job but have no money nor time for riding
what is eating your time? Are you putting in 10 - 12 hour days + commute time, if so you need to re-examine what your company is asking of you for insufficient compensation. Are you afraid of only doing a 40 hours work week? Are you being guilted in to thinking that if you dont do more you are a failure.? Are you performing in hope of gaining recognition or promotions, Has that happened?
You say you have no appreciable debt, only rent, so where is your money going? Really look at this. Are you dining out a lot, going and doing things that cost money like shopping, amusements, travel etc? Where is your money going that is taking it away from your desired life style (horses) . Have you looked at your job and the market. Are you being compensated on par with your peers at other companies?
You say you cannot afford the horse, Are you thinking you need a gold label horse experience and are unwilling to look at a more low key or modest situation?
Have you looked at your job in other areas of the country where your money goes further?
Are you prepared to take a year off and have funds enough to compensate for lost income and lost benefits? Do you have sufficient support if you get injured during a WS situation? Medical coverage Living expenses
are you prepared to face the what now of finding a new job when your WS experience is over?
does your job come with benefits like stock compensation and stock bonus? Consider this as part of your long term financial plan. DO you have a plan for 20 - 30 years in the future. Leaving a job like this can come with some financial gain or loss. Do you understand your compensation if your get stock. Do you have a financial planner helping with these details?
It sounds to me you are burned out in the wrong work situation and rather than seeking a new job or improving the situation and perspective of where you are, your are running back to a comfort zone of your younger years.
Is your company large enough that you have an HR person who can help your sort through your work life balance?
Personally I would not take of a year just to do the experience. I would examine my job and my approach to work. I would look hard at company work culture verses my work style. I would look at where I live and why. Is it as simple as moving to a location take cuts commute time , even if the community is not “all that” compared to where you are.
The twenties decade comes with some hard revelations about what it takes to have the life style we desire