"It's hard,” Cox, 47, told Cooper. “I probably caught up to this whole situation later than he did. And, I am really happy for him and he's got a girlfriend. Everything's great, I know it seems so weird, it's even weird for me to say that.”
Cox -- who earlier this month revealed to Howard Stern that she's been celibate since the October 2010 split -- told Cooper she she was "easing" her way back into the dating scene, with Arquette's support.
"I'm a homebody -- I don't really like to go out," the actress said. "I love restaurants, I love to have people over to my house. But I'm not really one to do a lot of stuff -- so I don't know how that all that happens... that part's a little difficult."
The former couple, who share custody of their 7-year-old daughter Coco, have reportedly maintained a good relationship post-split, both personally and professionally; in January, ABC confirmed that Arquette will guest star in the season finale of Cougar Town, which he co-executive produces with Cox.