I'm not very experienced in these issues, but here's my take:

Who are you planning to send a card as?

- His wife? He does not want to be married to you ATM, so that's out

- His friend? Do you think he considers you a friend (I know you mentioned this, but maybe you should ask yourself, anyway). Do you consider him a friend?

Also, he might see it as pursuing behaviour

Me 33, H 34
T 15 (on and off, 7 years this stretch)
M 4
DD 3
OW July 2010, IDLY - Oct 2010

1st sep 28/5/11-14/8/11 (my idea)
OW confirmed 25/11/11 (H travelled with OW 26/11/11)
I moved out 3/12/11