I wish I could offer you some insight, but I'm not familiar enough with the situation to offer any advice. Unfortunately, my only suggestion would be to post this thread under the Postpartum Depression Forum.

Postpartum Depression - Forums at Psych Central

Just know that it isn't your fault. It's most likely an issue that your mother has to resolve on her end before you can stand a chance. I truly hope you can find some comfort and more helpful advice in connecting with your mother.