Should I be depressed that I'm gonna be living alone with my grandmother?

Well my mom is moving back to Sao Paulo, and I'm really sad. Me and her never got along when she lived with me and my grandmother, and I never thought that I'd be sad that she's leaving. I think I'm mainly sad that I'm gonna have to live alone with my 83 year old grandmother. I know it's wrong for me to be feeling like this, but It's just a depressng ora whenever I'm here. Cause she's so old and it just feels like she's gonna pass any minute. I'm also 21 and have a daughter, and I would move out but I suffer from panic and anxety disorder so it's hard for me to work and save money to move out. I look at this as motivation to get on the ball so I can move out, but with my panic disorder it's gonna be SO hard. What can I do?