Stutter unintentionally makes me appear rude.

Stutter unintentionally makes me appear rude. Hi i just wanted to vent some pent up emotions. So a little history, even though my stutter was apparent from a young age my parents just always denied it. So ive always tried to hide it by blocking even from them and whenever I did stutter in my conversations with them they would just not engage me anymore. Though that happened less frequently because they got me into a military boarding school. For some reason when people see me initially, they expect a lot and I don't know why. It's always been the case and when I stutter it's like they're very disappointed. So all of this is just infinite fuel for my insecurity and so the blocking. I remember in college this girl was interested in me and while we were talking I was just blocking out words from my sentences, so most sentences came out very blunt and rude. She got the impression I didn't like her and was hurt and I thought that was easier than me having to explain my stutter. Fast forward to now, in my job most times I can't even say "Good Morning" to people and I just say Hi all the time. Since it's only been a few weeks, people just think I'm weird or rude. I want to say so much and I just can't. Even friends who know I have a stutter are understanding at first and then at some point they say " You know you have to work on that". Whenever situations like this happen, I just mentally shutdown now because I don't know how to deal with it. Edit: Thanks for suggestions and sharing your own experiences. You guys are awesome.