Moving out advise.!!):

Im 17 and in Texas you can move out at 17 as long as your mom lnows where you are. I need help in what to say to her im moving in with my boyfriends family we are engaged and have been for almost 2 years (2 years in Apirl) all together we have been together for almost 5 years and im living home due to family matters and my mom is mentally abusive and i cant take it anymore i need a nice way of telling her im leaving. Please help and no negitive comments.! Im leaving the 14th thats also when im telling her