Blimey Steve the guy you described above seems miles apart from the Steve I knew early 2000's! Good to hear your getting your life back, same with Diamonds, you've come leaps and bounds!
Really sorry to hear what your going through Pardeep, you know it will get easier, just takes time. When someone says 'it's not working' that implies perhaps it could with change, if someone wants to be with someone else they should simply (as if its simple!) 'I don't feel the same anymore' if its over its over THEN you can see other people, no morals people who cheat, selfish couldn't give a damn about the other persons feelings.
From what you wrote on here you gave a lot to the relationship, taking on the kids ect, you didn't deserve to be treated like that.
Z