"Following" and "favorites" relationship models in Rails---one master model or specific models for each relationship
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I'm working on an app where a user can have one of two kinds of relationships to other users---either `favoriting` them, or `following` them---and I suppose the reverse actions, `is favorited by` and `is being follow by` will also come up as methods I'll want to call.

What are the considerations I should have in making my user model?  Specifically, should I have one model, relationships, that specifies:

    Relationships
    user_1 | relationship_type | user_2

where relationship_type is `favoriting` or `following`? 

Or should I have 2 separate models:

    Favorites
    user 1 | user_2

    Follows
    user 1 | user_2

I don't know a whole lot about databases, so can I ask what are the considerations in choosing between these two potential setups?  Is 2 more normalized than 3, or less?  Does that matter?  Under what circumstances?