It can sometimes take a long time to find a horse that fits, but I have also seen numerous instructors go on a power trip or make students dependent on lessons by matching them with unsuitable horses. I'm not saying this is necessarily the case with your instructor, but that it does indeed happen. It is of course fantastic to have an instructor search with you for a horse, but you should also be heavily involved in the process.
Lately, I've become...a little disheartened? Sad? There are very few school horses at our barn, as it is small location. The few that are at the barn are kind, good horses, but below my current level. We've been resorting to jumping w/no reins and the such to try and keep things interesting, as these horses can't really jump above X's (due to age or soundness of the lesson horse). Most are walk/trot horses for beginner children- I'm an adult. I've tried to stay positive and to try and refine myself on these horses, but I am finding myself more and more disappointed.
I think you need to ask yourself two questions:
1) What are your goals for horseback riding
2) Is your current instructor able to successfully fulfill your goals?
From the above, it appears you already know the answer to this. You will come across this issue several times, if your goal is to keep progressing. Unfortunately, most barns will have a cap of what level they are able to teach, whether that be in the instructor's ability or resources available.
*Is it considered absolutely rude to take 1 lesson a week at another barn in the area? What is the etiquette?
This entirely depends on the instructor's personality. Some instructors take it very well, while others can take it as a form of insult. I've experienced both.
Do I have to tell my trainer? Can I get away with not mentioning anything? It isn't like I'm packing up and leaving my barn, I really like my trainer, but right now I feel like she doesn't have the time or the focus for me (let alone time to work with me on finding a new mount. I've mentioned to her that I'm getting a little unhappy with the lesson situation, dropped the hints that I'm EXTREMELY ready for her to find me a new horse...but it's all kinda waved away). My trainer even admitted our lessons are less than exciting due to lack of capable horses.
Short-term, you may be able to hide it, but probably not long-term. You will have to make the call on whichever you'd think would be best. In a situation similar to yours, I tried lessons at another barn 1-2 times and decided not to tell my trainer at the time. The trainer still somehow found out and basically told me that I could not train under them, unless I quit at the other barn. Now, I don't think the situation would have been any different if I had told my trainer that I was trying lessons at another barn, but It may have possibly made the situation a bit better. However, I was only 15 at the time and was not confident in having that sort of discussion. The trainer offered alternatives, but ultimately I ended up leaving that barn on a sour note, far too late. The trainer just did not have the resources, despite them trying to insist that they did. Afterwards, I came to discover that this was not abnormal behavior for this trainer and I was not the only client this had happened too. In fact many had looked elsewhere for further learning opportunities and encountered the same frustrations and hostile behavior. The moral of this story is that being upfront is probably most ethical, so the trainer has a chance to try and accommodate; however, it may not change anything. Ultimately, the best decision may be to thank the trainer for their time, try to leave things on a good note, and find a barn that does offer what you are looking for.
I'm just looking to get some time jumping some more capable horses. There simply aren't any school horses that fit the bill at my current location and I don't feel like I'm improving myself. I have another barn in mind, but I know my trainer knows at least one trainer there. They at least wouldn't know me, but if I said who I have been riding with, I'm sure it will be brought up eventually, so not sure if it is better to be vague about my experience. Or if it is just better to not ride at two places in the first place...I loathe drama.
I personally feel like my trainer will be mad at me if I mention I want to take lessons elsewhere. My old trainer years ago was livid if I ever lessoned with someone other than her when she didn't have time for me to even get a lesson in with her every week due to her crazy schedule. I just don't want to burn any bridges or rock any boats. I just want to enjoy my jumping lessons again with a horse much younger than 30 years old...
It is possible that your instructor could get mad, but do not let that stop you in making the best decision for yourself. Lesson barns are a business and instructors will often try and hold onto their clientele as long as possible. However, you have every right to look elsewhere if you are no longer learning in the lessons you are paying for. Sometimes, this may have undesirable consequences, but that will not be your fault. All you can do is be as kind as possible, before moving on and the rest is up to your instructor.
This isn't to say that I WOULDN'T switch barns in the future. Frankly, if more months go by and I haven't heard a single word about a possible horse to even look at, I'll probably have to move on. I just don't understand how much time is normal to pass by when you've made it known that you are open to buy, but haven't been shown a single animal via video or in person. Do people just not sell horses in December/January/February? Thoughts on that? Is my trainer possibly just...not focusing on my needs at all? I'm getting a bad feeling about it, honestly...but maybe I'm too over-eager and chomping at the bit (and need a reality check)!