Interesting read. I fell upon this old thread in search of something completely different.

This thread speaks to me.

When my daughter and her SO (of 7 years) were together they made a choice together not to have children. Taking pets into their lives also came with great discussion about responsibility - including what would happen should the relationship end - which it unfortunately did.

As with human children they have a scheduled custody arrangement. As with human children this neccessitates regular contact and communication between the ex partners.

I commend the both of them for thoughtfully considering this before taking on the responsibility of 'pet parenting'.

My response to the original poster is to find understanding in his girlfriend that this is about just that - being responsible. It would be completely wrong and irresponsible for her to ignore her ownership duties. Ownership doesn't stop merely because one party has custody.

Coming into to contact with her ex in order to make this transpire is part and parcel with that happening. You need to respect that. To suggest the whole reason she is spending time with the pet is to insinuate herself into her ex's life is unfair and suggests a problem with trust and inner security.

This thread is two years old. I genuinely hope all worked out and that the OP was able to welcom the pets as part of his own family.