That makes sense. They used to just kind of coddle those folks along because they were a nice guy, close to retirement or to keep the numbers up for a deployment. But keeping that dead weight is expensive, and so are retirement benefits.
You have absolutely no reason to be embarrassed about the broken engagement. That's what dating is for, and good on you for getting premarital counseling and taking your time.
I think military relationships tend to be intense, with long work hours and periods of separation for training, schools, deployments, etc. the time you spend together is almost like a different life. I think there is also sometimes a feeling of pressure to marry so that you can ensure getting stationed together (plus the extra $).
Really glad you reached out here.