*confused screming*

I'm putting this in spoilers because I am very sensitive right now.

Most people come together on thanksgiving to be around family and friends. telling people around them what they care about the most. why they love so and so favorite foods and so forth. well, today instead of anyone telling me what they are thankful for I walk into the kitchen and my adoptive mom starts up a conversation. for background, I have lived with her for almost 7 or 8 years now my bio mom gave us to her because my bio mom couldn't keep me without DHS getting involved for all intents and purposes let's call adoptive mom. Mom2. Well, today of all days mom2 desires to tell the rest of the family while I'm in the kitchen the reason why she gives up on me. she says it is because I never do what I'm told and since I ship out to the military in 6 months she gave up on being helpful to me in any way. while I might not always get up then and there to do what I'm told I always get it done. ie mowing the lawn it might take me an hour to get out there but that's because it's the heat of the day and OK summers get hot af. but she told her family that whenever I'm asked to do something i tell her "fuck you" to her face. I have never said those words once to her in any way shape or form. and according to other people they are surprised how i am grounded all the time because i have As and Bs in school i dont do drugs I have never gotten into a fight im in the military and i cook clean the house mow the yard do the laundry and more. but i can get grounded for over 3 months at a time over something small and stupid in everyone's eyes except mom2. long story short i wonder what i did wrong for her to dislike me like this (i dont know if i should put hate or not) it seams like no matter what i do its never right and im always in the wrong. its gotten to the point where she will go to my teacher if im doing wrong at home because i trust said teacher a lot. so the big question is this... am i just a burden to her and those around me?..
thanks for letting me talk it out...

p.s. this is completely unrelated and maybe a happy note? but my Grammarly has underlined 23 different words in that paragraph above and i find that funny.