Pip is an orphan who has never met either his mother or father. In the beginning of chapter 1, Pip tells us:
“As I never saw my father or my mother, and never saw any likeness of either of them (for their days were long before the days of photographs), my first fancies regarding what they were like, were unreasonably derived from their tombstones.”
Therefore when Pip thinks of his mother, he thinks of a headstone. He has never even seen a picture of her.
Pip is raised be a hard, cruel sister who beats him. She married a blacksmith, Joe, and raises Pip “by hand” with “Tickler” the stick, with which she beats Pip regularly.
The first kind woman in Pip’s life is Biddy. Although Biddy is not much older, she cares for Pip and teaches him. She eventually marries Joe, making her a kind of mother to Pip since he is as close as anything to a father for Pip.
I don't think anyone reminds Pip of his mom. Joe is a father figure to Pip while living in the forges. When Pip moves to London I think that Jaggers replaces Joe and acts like a father figure. What is ironic though is that Joe and Jaggers are so different. If there is someone that reminds Pip of his mom I would have to say its probably Biddy!