Oxytocin Levels ? My 54 Yr. Old Wife Has Had

oxytocin levels ? my 54 yr. old wife has had a young lover some 17 yrs. younger she did not cheat we discussed first. penis size is quite a change from mine. longer 'much much thicker huge balls head is very big.now she says she's fallen in love with him. the " love hormone" is it real and is size the cause of this? HELP US PLEASE