A big part of your ‘true’ income is the cost of living where you are working. There are eye-popping salaries available in many fields in cities such as San Francisco and NYC, but the cost of housing, transportation and everything else means that even a single adult could barely survive on that money.
It may matter less how much you make than where you are located. There are smaller population areas, with much shorter commutes and lower housing costs, where it would be possible to comfortably keep at least one horse on $50k/year. And there are areas where it would be very difficult to keep a horse even at $75k/year and up. Not just due to different costs of keeping a horse, but due to different levels of housing costs and other costs of living.
In areas where you end up living 45 min+ from your work, due to the cost of housing closer to work (this is common), the commute will eat up much of your horse time. That’s 1 1/2 hours every day just going to & from work (equivalent to almost another full work day each week). You may also have a lengthy commute to your horse. And you might have some other things you want to do with non-work time. And you might even want to pursue a relationship that also needs time. Even if you are willing to do the driving and load the miles on your car, there will be days when the demands of work won’t allow you the time for a lengthy drive to your horse. If you can manage the “itty bitty apartment in the city” lifestyle to be very close to work, it might be more do-able. (There used to be a blog about that, don’t know if it is still going.)
Do careful research on the areas you are thinking about living regarding the specifics of what life with a horse would be like - distances; drive times; what you could afford re housing, as well as board locations and costs.
This might be a time to do a riding arrangement other than horse ownership, something you can easily cancel or modify, until you work out the realities of ownership.
Good luck on working out a happy life, wherever you go!