I still stay in contact with my in laws. My XW will not control who I will talk to or remain friendly with. That is MY choice not hers. She may get pissed but that's her problem to deal with.
So it really is all a personal decision for you how you handle this and anything else in the future. I do plan on going to my X MILs funeral as long as I get at least one invite.
Me:48 W:55 M:22 T:23 Bomb:19Nov09 S:15Jan10 D:11Feb10 EA:Confirmed on 20Apr10 Fast track to her divorcing me