Trixie,

A couple of questions:

1. How old are you, Tom and Harry?

2. Were you and Tom ever married?

3. Is your daughter with you and where are you two staying?

It seems to me that you and Tom were thrown into a stressful situation at such a young age.  Under those conditions then of course that the relationship would be hard to hold together between the financial pressures, being parents, the lack of time and opportunity for either of you to grow up (college, dating others, etc.).

Have you two tried couples counseling?  Before you throw the baby out with the bath water (excuse the metaphor) with your relationship with Tom, it seems that you two would benefit as a couple and as a family.

Harry is the new guy which seems like someone who can be the fun, non-father, non-provider, no responsibilities guy to rescue you.  This is only 3 months after separation.  I think you would do your commitment to your family and relationship a disservice by not working your issues out with Tom.  Jumping to another guy is the easy way out in my opinion.

Mark