Whatever reason? It's because they are white - that's the reason. And any attempt to reach out to them would piss off all of the racial spoils system players loosely clinging to the Democrat coalition.
They made the decision to turn themselves in the party of aggrieved minority groups - they can't complain now when the majority no longer wants anything to do with them.
They manufactured the grievances thereof as well, by destroying the traditional family in these minority enclaves.