First good on you for adopting!
I think the first thing to change is this-
Usually when we try to pet her, we try to pet her twice and if she’s still resisting we leave the room
Basically in all animals (humans and even single celled organisms) –> “Action+reward=action will be continued”. If she’s shy she likely views you leaving the room as a reward. So she resists twice and you leave-so she’s now learned all she needs to do is resist and you’ll go away-then she can be with her man in peace.
I’m definitely not suggesting force petting her or anything like that. She’ll need patience and time -but instead of trying to pet her and then going away try a different setup.
When she comes up for a treat, sneak a quick pet in, then give her a few treats and leave her alone. Over time you can increase how much petting or interaction and she’ll slowly learn that petting from you=treats=a good thing.
One of my bunnies learned from her bonded mate to beg. She may be able to do this too. i.e. pet your male and give him treats-and let her see this.