A 180 to put yourself last. Wow. This is tricky because you also want to take care of yourself right now and be happy. Maybe a 180 of not putting yourself last, but of others of equal importance to yourself?
So it sounds like you see yourself as the stereotypical military man, or that others do.
I think the softening the image may have alot to do with what's inside as well as outside. There should be a ton of opportunity for 180s here. You don't have to be a wimp to be soft on the edges.
Can you grow your hair out a bit so you can style it some? Purchase some nice business attire...maybe try to get some basics to build upon, like the khaki slacks, a nice suit, some dress shirts and ties?
What about your manner? Can you soften your communication style? Can you show a more empathetic side of you?
Things you do...can you expose yourself to different situations and hobbies in which you nurture that softer side of you?
I think to be softer, look at it from all angles. Don't drastically change who you are, or try to overnight, but maybe start to work on a few of these things at once. I think this is a fabulous opportunity for you to do a good 180 that you will be happy about. Also, maybe it will help if you can find some non-military folk to hang out with some, if you want to step back a bit from the macho military stuff. It's amazing how much those around you influence you and you pick up their mannerisms, etc. Broaden your horizons a bit, if that makes sense.