Being a mom and a mogul isn’t easy, just ask Jessica Simpson. The singer and fashion designer, 43, splits her time between LA and Nashville, where she’s currently working on new music. Jessica and her family spent the summer in Tennessee, but once the school year started, husband Eric Johnson and their three children, Maxwell, 11, Ace, 10, and Birdie, 4, returned home to California. “I’m back and forth a lot, so now they know what it’s like to miss me, and I feel very loved,” Jessica joked. All kidding aside, a source says she does struggle with mom guilt over spending two weeks at a time apart from her children. “Jessica is trying to do it all. It’s been hard but gratifying for her,” adds the source. “She wants…
