backfired?

as a child i distinctly remember that my mother would always purchase the things we needed to ensure we had our own. i always thought it was so we wouldn't have to borrow from others and in turn 'bug' them. but i really don't know why my mom did it. but i am thinking the intended effect did not take. as an adult i have a hard time letting others borrow things. i always think to myself 'give it back, it's mine - get your own' - i never actually say these things because i know rationally 'how' to share, i just don't wanna.