Back to work.

Has anybody else gone back to work before your 6 weeks was up? I'm struggling at the thought, I've been a stay at home mom since my oldest (2) was born, then I had his brother (1) and now their sister who's only 3 weeks. My SO decided that he was leaving the kids and I. I'm literally starting over from scratch with nothing to my name, I cant afford to stay home for 3 more weeks. I've never been gone from my kids for more than 3 hours, on top of that I'm EBF my 3 week old and havent even started pumping so that I could save because he left so suddenly. I wasn't prepared. I had an interview today and they're making it sound like I'm starting ASAP and I'm just so sad and stressed. I let him know I got the job and he told me "well idk how you're going to do that because I wont be available to help with them" which stressed me out even more. Mostly I'm just worried about leaving my baby so soon. I know my boys will be ok and play all day at grandmas but leaving her so soon is really driving me crazy. Has anyone had to do it? What was it like and how did you keep up? With two toodlers and a newborn it's already so hard. Add a full time job + school and I just have no clue how to do it.