Does this get any easier..

I’m a FTM who just went back to work this week, my LO is 13 weeks old. The first day, I was fine. Felt like a “mommy’s day out”. Now day two and three, I feel so depressed. When my husband leaves to go drop her off at daycare I just sob and I’m so depressed. I’m in the process of finishing my PhD but it’ll be a few years. I just feel so empty without my baby, it feels so unfair. Does it get any easier/better?