Do they do it on purpose

Is this normal but it seems he is living the life with her that he claimed he never wanted with me. He told me he didn't want to 'tie outselves down' with a dog or a house or kids but now he's gone out and got the dog and house and treating her kids like his own? Also he blocked my number cos I want my stuff back but after 3 months he has now unblocked it. Is this all part of their 'game'? Despite still being hurt (bitter, I admit it!) and sometimes missing the person he never actually was, I thank the universe everyday that he met someone who is more willing to put up with his mental and physical cruelty than I was....yet i still have all these questions! Lol.