The Hades crossing your 7th, etc. also can mean relationships that 
    'deteriorate' and/or relationships with 'down and outers' of some kind 
    -- i.e. poverty stricken, chronically ill, depressed, or stuck-in-the-past partners. 

    However, it ALSO can mean that your 'relationship' with each other can
   'bring out the past' in both of you, as you mentioned (especially probably as it 
   aspected your Moon.) I would guess that 'doing research' together, if 
   that's what part of your partnership with 2nd boyfriend was/is about, 
    would be a positive manifestation. 

  Hades can also bring out elements of shame, embarrassment and feeling 
  demeaned, etc, through others. 

[ More material on the Moon / Hades is welcome.    -  Steve ]