You haven't let your D down and shouldn't feel guilty about any of this.
I agree with Rob that your H is grasping at straws. Don't let him use you. I can see him moving with you and this continuing whilst OW decides what she is doing - don't let them try to do that to you.
The fact that you can view OW with sympathy is just amazing and shows what a big person you are.
I must admit I am a bit suspicious about your H's offer to help you move a bit earlier....I can't forget his keenness to get the deposit on your current rental back. Be careful Sue.
Saffie me 46 H 46 M in 1986 D20,D18,S16,D13 H's A 01/05 to 07/06 H recommitted to M 07/06 renewed vows 09/06 Going from strength to strength