Cheating...

Ive been dating my current bf 3 months now. On friday my x husband and I had to put our dog down due to fatal illness. This devestated me. Through the grapevine my x boyfriend heard and stopped by to offer support. (He is friends with both my x husband and current bf and stops by quite often.) He hugged me, held on, kissed my forehead, let me cry. Offered to go with my x husband and I to the vet to let our dog pass and offered to help dig the grave. Meanwhile my bf's response to this awful news was "wow sorry babe" and a brief hug while saying "you havent got all the crying out yet?" My bf stayed home not wanting to participate in the funeral or support me through it. After everything was done I was intimately comforted by my x bf... idk wat to do... my x bf and I DO NOT work together (constant fighting) but my bf now obviously failed this relationship hurtle. Im heartbroken, confussed, and guilty. :( advice?