This is a harder one to give advice on for everyone rides and trains differently. Every trainer has "their way" they like the horse to go and how they teach them to get there. I would start by being open and honest with your trainer, after all her job as a professional is to help you as well as your horse. I would prefer that a client be open with me and honest about their frustrations so we could work on it together. Half of the job of a "trainer" is the horse and the other half is to teach you how to get the most out of your horse, for it does no good for your trainer to get your horse to lope and then send them home to you if she hasn't taught you how to get the same out of him. Keep in mind that you do want your horse to go better for the trainer, otherwise you wouldn't be getting anything out of it, but you need to talk with her and try to come up with a good way for you to learn his buttons before he is sent home.
My only concern out of that e-mail is that it sounded a little like she was going to try and rush to get him "finished" to send him home. A two year old is like a child, they all learn and progress at different rates, and some do take longer than others. I would be a little concerned about the comment of pushing and time crunch to get him "done." I only bring that up, for I see the results time and time again with the horses who are pushed a little to fast, it is my own pet peeve if you will, just due to the number of horses that have come in with issues due to being rushed instead of letting them come along on their own terms. I am not against showing two year old futurity horses, but not every horse is ready and mature enough at two to be at the same level. I just had to throw that out, for that concerned me a little with that comment.
My only real advice is to talk with your trainer and tell her your frustrations. A couple ideas I would throw out if you were my client would to have you come ride another horse to work on getting the lope cues down solid, and ask your trainer to ride another horse, or even your horse while you take a lesson so she can show you and demonstrate exactly how to cue and what your ideal is. I would also recommend having her "warm up" your horse for you so you can see exactly how she does things and then have her ride another horse along with you while you ride your horse. I do most of my lessons while I'm riding, just for that exact reason. It is a lot easier to teach someone if you can demonstrate while you explain how to do something and they can see exactly what you are trying to explain versus trying to understand without a visual. I might also ask your trainer to work hard on you with your horse prior to taking him home so you are prepared and feel capable once your horse is home. She should understand and be willing to help you "get the lope" before you take your guy home.
Hope that helps some.