The coldness in his tone didn't bother Lily, nor did his assertion that she had been judging him in any sense. She knew she hadn't been regardless of what he thought. And the sheer idea that he assumed she was blind to how Sirius felt about James was ludicrous. By this point in time the only people who quite possibly didn't know were James and Sirius himself. "Of course, and I'm not surprised to see that presumption is going both ways in this conversation."
She wasn't going to explain herself to Regulus. She was content to allow James to handle things with Sirius when the time came.
"I see that now, and I apologize for thinking you might." She almost laughed when he referred to her as 'Mrs. Potter' considering the words that followed. "My congratulations to both you and Remus. I hope you both find some happiness together. As for what I may or may not be ignoring, you seem to have quite a few opinions on my marriage when you only got to see a brief glimpse of it. How I choose to handle my life, my marriage, and my friends - while I'm sure is a fascinating topic for you - is none of your business. Although, I do appreciate your warning, if that's what we're calling it."
She glanced at the watch on her wrist. "Well, I do believe I've taken up quite enough of your time. Good chat."