How to detach myself from my mom

I am currently 22 years old & have decided to move out because I feel like I’m at that age where I have too.. my mom is a single mom I honestly feel like we are so attached to each other and I knew that once this day came it would be super hard. I feel bad leaving her just because I know she’s alone with my 2 younger siblings, me being the oldest I’ve helped her a lot. I’m not in a rush to move out and would love to stay at home but how do I prepare myself once the day comes?