Coming from someone that has been in for 3 years. It’s going to happen all the time. You aren’t around people from the same town as you anymore. Instead it’s people from all over the world, with different goals, attitudes, etc. I currently work with an individual that seems to have it out for me and in some way always makes the comment that “oh he’s going to be an officer” or things along that nature. It’s obviously negative and comes off slightly jealous at times. If you easily get offended or your feelings get hurt, take this time to work on that because it’s just how it goes.
It's important to remember that just because you work with someone and may be friendly with them, that nobody likes to see others succeed beyond them. The person you're referring to probably doesn't even realize that they're undercutting you or alienating you from your work center, they're just trying to characterize you in such a way as to not feel like they need to compete with you to not feel bad that you're doing something with your career and they aren't. You can either ignore those people or address them by either telling them they don't need to treat you like that or getting them thinking about making career moves themselves. I've seen the exact problem you're describing with some of my junior guys before, and, like you said, it comes from a place of jealousy - they are projecting their feelings of inadequacy onto you. My only disagreement is that people either say destructive things because they are comfortable saying them or they don't know they're doing it, and the person who wants them to stop has to do the uncomfortable, unpopular thing to address them and so usually that behavior goes unchecked and we just tell ourselves that it is what it is.
PM me if you need to talk about work center problems, but also consider mentioning it to your LPO or chief, they've all dealt with it at some point.