What about the other side of the coin - did Marc make any mention about you staying in the same house and that he was your landlord etc? If he made no mention, that seems completely bizarre as well considering you 'shared' a house for over 1 1/2 years.

Maybe he performed a psychiatric trick on you, hypnotised you so you would forget about him, his car and living with him... and you didn't realise until recently!

That does seem really weird though!