Re: how to build trust/stop worrying!! THE LOOP AT THE END!!
Hmmm... Does she want to be with you because she wants to spend time with you, or because she wants to make sure that you don't catch her cheating?
I'd go with your gut instincts on this one. The whole thing is shady, including the wanting to spend every moment with you. It positively reeks of her still seeing her ex behind your back. Sorry dude.