Gabriel did not "take Martha from everything she knew." Her fate is result of her own actions and choices. Like Nina she took a chance and she lost. Those are the breaks!

The condoms didn't work. That's why Claire joined the cast at the end of season four.

They broke. That's why Claire is in existence!

Stan wouldn't necessarily recognize the disguises in the photos. One other possible explanation is that there was a hired photographer who very convienently announced that none of the wedding photos turned out! Oh silly well….

I'm sure after last time the Jennings parents have learned to lock their bedroom door before they start having sex.