One or two of you are struggling to follow the relationships, and I don't wonder. So I am providing a few online resources that may help.
There's a PDF family tree here that I think is quite cool. At least it shows Constance which is more than some of them do.
There's another on Wiki here
If nothing else, these should point out the extreme thinness of Henry VII's claim to the throne!
If you would like some more meaty reading online, I suggest a look at Michael Miller's Wars of the Roses. I don't necessarily agree with all his conclusions, but as a convenient starting point for the era, it cannot be bettered. If you want to know how the kingdom's finances worked, or what a Great Council was about, the appendixes are well worth a look.