moving out

hi, im nearly 18 and my mum has been so mentally draining so much that I dont want to live with her. I cant stop here but I have agoraphobia so its so difficult to know where to go. ive started going in to shops and can talk to people but i dont go very far from home. im able to walk places and am slowly getting better but I find car journeys the worst and the only way I could practice is with my mum. my dad lives in another country so thats not an option. does anyone know what i could do maybe in the meantime to get out or when im 18 and what options i have.