I lost my mother a few years ago to cancer. As my friend (who'd lost his mother in the early 70s to cancer) warned me beforehand, the grief never goes away, whether it was 30 years ago or just three, it will always be there. Sometimes you can go hours, then days, then maybe a couple of days, but it's always there. There is nothing like losing your mother. My heart goes out to you.
One mistake I made was letting my famility dynamic change too dramatically. My mom was the "it" girl for planning and now we've drifted apart.