Confused about character(s)

I started watching the Netflix show Eric. I have a moderate case of facial blindness which makes it sometimes to follow shows because the show assumes the viewer recognizes who the people are and often I can’t.

What I need to know is if Vincent’s mom is the same woman who is the sister to the detective’s boyfriend. If it is the same woman, this complicates the story. If they are two different people than the plot is very different. I think Vincent’s mom is older than the other woman but still they look the same to me. Please help. Sorry for any spoilers.