"Meeting someone where they're at" basically means accepting others for where they are at on their life's journey, warts and all.

It's a little odd that your mom says she raised you "to meet people where they're at", yet she doesn't extend that courtesy to you.
Where you're at is you are not interested in someone who hasn't shown much interest in you.

Ask her to meet YOU where you're at.

There's no right or wrong in wanting to meet your father. There is simply a choice. Your choice.