How wrong is it to stay put until moms condition becomes desparate?

My mom has been dying for 4 years, including remissions and relapses--the first time re. which I dutifully quit my job and traveled 1500 miles just to be there if she needed me. Sucked that she only allowed my help twice that year ( i rushed her to hospital at night and stayed with her, made sure she got proper care), but whatever. Now, as it REALLY can't go past a few more months (i think???), should I quit / travel again, and end up putting my life on hold another year just "in case" something happens? I lost my first racehorse because of this, which was my livelihood. Now I risk losing the other, who is not only my livelihood but who will be my only comfort and companion when mom passes. No family left in this country. Would it be horrible to continue to race the horse a thousand miles away, and not fly back unless mom is admitted to hospital for good? or fly back now just for companionship "plus". One friend says to sell the horse as I can always get another. Another says to ask mom for help with my financial losses while I attend her (mom is wealthy--I have been getting financially worse since traveling cross country all the time to help her). I have a feeling either way I choose I'll have regrets. What does everyone else think?