Work hard for promotion, targeted by my NCO

Hey I'm kinda new here so I was hoping to get some good suggestions or advice on something that has kind of devastated me today. I am active duty military stationed in Hawaii. It's a great place but not in my case for now at least lol. I have went to Okinawa, Japan to deploy with a unit to Afghanistan to gain more experience in my job and also hopes to gaining an edge on any competition I'm up against for promotion. Needless to say, I have been getting screwed over majority of that time. So I came back to Hawaii after my deployment in Afghanistan and went on leave. 2 days right when I came back from my leave they threw me out on a training op in the field which is not smart on the chain of commands part at all. I was automatically starting to loose my motivation in pursuit of my promotion but still have high hopes.

Just to cut to the point I got sent out to the weapons range about 3 months later detached away from my unit to start working in support of another unit. So just today out of nowhere this Corporal that I don't even work for anymore came up to my Gunnery Sergeant talking about me and told her "Bordelon kind of just seems like a **** bag, he always looks like he's lost, and I think he's just too in mature for corporal. So I think it would be my responsibility to non recommend him".

Now I am engaged and I've been working very hard for a very long time thRough hell and back for this promotion to help out me and my soon to be wife financially stable when she moves on island with me. And I have passed all my training and obviously more experienced than majority of my competition here and never ever been in trouble for anything and great proficiency and conduct scores. But after hearing that from someone I was working with above me I'm starting to just loose hope faster than I have ever gave up on anything in my life, I'm a very strong willed person but that was almost instantly life changing to hear that after all that hell I've been through.

Sorry for the very long output.

It sounds tough... just letting you know you're in my thoughts