Relationships

I do not understand why a world renowned application such as Microsoft
Outlook Contacts seems to miss out completely that contacts are generally a
network of relationships. I also do not understand why there are no third
party software add-ins created by Microsoft that are able to handle a Family
tree like structure within contacts.
Please can someone tell me if there are any other products out there to add
on to Outlook where by I can edit a contact and assign a relationship ie;
Spouse, Child, Sibling, Parent and then view this network.
The problem with most grouping applications is that they are unable to
handle both "Spouse" links and "Dual Node Ancestry Links".
I really do struugle to understand why such an important and to me obvious
function is missing from Outlook or indeed any other Microsoft product
related to it.

Sebastian