Relationships, when they go south - waaaaahhhh!

Tweet

My partner of many years has just told me that everything is wrong for him at the moment. He has 2 children from a previous relationship who reside with their mom while I have 3 who reside with us. Together we share an additional child. His kids now refuse to come for their alloted fortnightly weekend sighting that they don't enjoy my children's company. My partner himself now says that he doesnt think he can continue to be a parent to them. He says that to be fair to me and to his kids it is best to end our relationship. What do I do when I don't want the relationship to end but can't see how it could posibly go on? Has anyone else had a similar experience or been in the same position of not wanting it to end? Or has anyone just got some advice for me? Thanks.