wa'alaikum as'salaam
Getting over someone is not as easy as tossing an old shoe out the door. The longer you are attached to them the harder it is to let go. It's kind of like being attached to the duniya and it's glamour. No one really wants to give it up. Here's my two cents inshallah.
To love someone means to get to know them upclose and personal, which means to break all or most islamic rules and norms to do the haraam (being with a non-mahram) to let it go that far.
Not sure what your family said to him but if it was to protect you then they did the right thing; what they said or how they said it might be another matter.
If he was sincere about you then he could've tried to work things out and do it the right way by talking to your parents and revealing his intentions rather then run off to another girl.
lastly, the time it will take to forget him depends on you. how much are you willing to let go and how attached are you. You have to remember he and everything else in this duniya is temporary. We can't displease Allah to please our nafs and if we are patient and do what is right then inshallah we will be blessed with something better.
My advice is to inshallah try to devout yourself to Islam more, read more, increase knowledge more, sit with righteous sisters more, and do dhikr more. Ponder over your past and see how islamic vs unislamic it was and what are your strengths and weaknesses and use your strengths and work on your weaknesses to make yourself a better person and a better servant. Our aim is to please Allah, when we start working towards that then other duniya matters seem trivial.
oh and yea, make dua for yourself