Anyone who’s ever been through a bad breakup has got to give credit to Alliance Data Systems. The Dallas-based credit card transaction processor ended its $6.4 billion agreement to sell itself to affiliates of Blackstone Group. And it added this message: “It’s not me, it’s you.”

To drive home that point, ADS is asking Blackstone for $170 million.

The two companies agreed on a deal last May. A month ago, ADS sent notice that Blackstone, which has been battered about by the market turmoil and seen its stock decline 40 percent since its IPO, was in breach of the terms of the acquisition and wasn’t using its “best efforts” to complete the transaction.

This is just the latest legal salvo that ADS has fired across Blackstone’s bow, in a courtship that long ago went sour. As the Daily Deal points out,

Alliance Data first sued in January to bring Blackstone back to the negotiating table after the New York-based private equity firm said it did not expect the deal to go through due to onerous federal regulatory requirements. Blackstone balked at demands from the Office of the Controller of the Currency that it provide a $400 million guarantee of credit support to an Alliance banking subsidiary that the OCC regulates.