Living with mother in law

My significant other and I are planning to move out of his mom’s place & get a place of our own sometime within the next year. I told my family our plans and they’re against it because they feel bad for her. She lost her husband a few years ago and her other son barely speaks/visits her, in a way she pretty much only has my significant other.

I feel kinda bad for wanting to leave since she’s going to be alone but i want a place of my own with my SO & I, have freedom to do things. Plus, my SO and I visit my side of the family at least once a week & well def be visiting his mom weekly too. Anyone else ever go through anything like this? Should we wait longer to move on? Or am I just being too concerned?