Is this irresponsible?

I want a horse. I grew up with animals, I’ve had four horses, and miss riding. Me and my boyfriend just bought a house with 10 acres. I can’t afford a horse on my monthly paycheck. I make $2,000 a month.

So I want to get a “second job”. I have worked online before and would like to get something to help me make the payments (it’s about $300 monthly not including unexpected fees). Is it irresponsible to get another job and fully rely on that to make the payments to keep my horse? We have 3 dogs but since riding is my hobby and passion my boyfriend said he would help with food. (I have about $190 in savings after all my bills with my regular job but wanted to keep that for emergencies/savings). I just don’t want to look back and realize that I never got to continue what I loved because I didn’t want to go for it. I already have stalls and everything from my last horses so the only expense would be food, supplements, water, and trimmings.

I don’t want to be irresponsible but I also want it so incredibly badly.