I'm less optimistic than the other people responding that this is a phase that will pass. NRE certainly makes people make bad choices about their relationships sometimes, but...
Originally Posted by ArchiePunker
she wants to maintain a relationship with me but, not a romantic one.
...that sounds like someone who has met someone else and is moving on, not like someone who has met someone else and is too distracted to maintain their current relationship(s).
I'd take her at her word, and try to figure out how to make your life, and co-parenting, make sense for you now.