How do I become more motivated an interested in life?

I've been staying at my mothers house and my mother is really depressed and I'm adapting I literally just stay in bed all day like she does and I starve myself like she does and when I eat I eat all sugary foods like she does and I try to eat nutritious foods like I had an apple and I'm planning on starting a sewing hobby but I have to find a desk first for the mahine I feel like **** all the time and this isn't like me I usually take really good care of myself but I'm just so demotivated I want to start eating clean again and going for walks and stuff and cleaning and cooking but I just hate everything and it causes me pain