She's right, there is no money in horse boarding. Boarding usually just makes you enough money to pay for the feed for all of the horses (your own included) and the barn help. It's hard to charge enough to make any money and still be competitive in price.

As for training, you can make money in it, but the people who do are top notch trainers showing horses at the big shows. Trainers working with intermediate riders and "starting horses" are a dime a dozen. You have to keep your rates low to compete. But, specialized trainers who can get horses to win at the upper levels are not as common and can charge more.

Getting to the level of a specialized trainer takes a lot of time and money though. You have to have the resources to bring a few of your own horses through the levels and train them yourself. And those horses have to win at the upper levels of competition to get your name out there. After that, you can slowly start building a clientle. It will take another few years to be able to gain enough clients to really make some money...

So no, there's not a lot of money in horse training, lol.