Unfortunately, Miss Havisham's only experience with love was also paired with heartbreak and betrayal. She loved her fiance unabashedly and with total abandon, and he ended up betraying her completely. He did not love her; he was made of ice, and had his own intentions and scheming plots for her. This was all that Miss Havisham knew of love, and it permanently altered her perception. She in turn passed this on to Estella. From the time that she was small, she indoctrinated Estella, teaching her to hate any form of affection, emotion or love. As a result, Estella did not know how to love; she couldn't grasp it or comprehend it. Miss Havisham admits that she,
"with my teachings, and with this figure of myself always before her a warning to back and point my lessons, I stole her heart away and put ice in its place."
She trained Estella to hate emotion and love, and to be cold to its influence. This is very unfortunate for Pip, who loves Estella with all of his heart. She can't return that love, and makes a bad marriage because love is not a factor for her. Pip is crushed, and Miss Havisham's definition of love keeps Estella and him from being happy together at first.
When Miss Havisham tells Pip, in the beginning, to love Estella, no matter what she did to him, he does. Estella is mean, condescending, cruel and distant, and Pip loves her anyway. That definition of total and unconditional love defines Pip's love for the cold Estella completely.
Joe's relationship with Pip is one of total unconditional love of a parent for a child. Joe loves Pip, and Pip, after his expectations, rejects that love and is ashamed of it. He feels guilty for this, and eventually repents of his cold behavior. He, for a while, played into Miss Havisham's rejection of love, but that does not last, and he and Joe make up for the distance they had in their relationship. Through it all though, Joe loved Pip, even though Pip distanced himself from him, and was embarrassed by him. Joe loved Pip the same way that Miss Havisham implored Pip to love Estella. I hope that those thoughts helped a bit; good luck!