In September, Fergie and Duhamel, 44, confirmed to PEOPLE exclusively that they were going their separate ways after eight years of marriage.
“I love Josh, he’s the father of my child … You’re making me cry,” the singer says to Williams of their 4-year-old son Axl Jack. “We forever have that project together and we’re doing the best we can.”
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Williams also explains that Fergie and Duhamel have been separated since February but they tried to figure out their relationship before publicly confirming their separation.
The pair’s split came as a shock to many, but some who know them best said they had been traveling down different paths for a while. “They have been leading separate lives for a long time,” a source previously told PEOPLE in September.
“With absolute love and respect we decided to separate as a couple earlier this year,” Fergie and Duhamel said in a joint statement to PEOPLE about their breakup. “To give our family the best opportunity to adjust, we wanted to keep this a private matter before sharing it with the public. We are and will always be united in our support of each other and our family.”
Fergie’s appearance on The Wendy Williams Show airs Thursday (check your local listings).