He really sounds like he did a good job at isolating you, and shame on your family for not sticking by YOUR side, through whatever struggles you have been through.
I agree, about not turning to the other guy, not right now, until you've got this catastrophe of a marriage all sorted out. Are you screen-shotting these FB blasts that are defaming you?
He is playing the victim. And every misstep you take, gets blown into an over the top smear campaign. Poor him. What about poor you?!
How are the kids doing through all of this? Are you keeping up with your studies, and what are your plans for being an independent single mom? Kids would resent your rushing right into a new relationship, post separation. You need time to heal from all of this if you do choose to divorce.
Someone mentioned here, before and I agree with their words, wholeheartedly, sometimes coming from a broken home is better than coming from a dysfunctional one.