I can’t call out because there is no one to cover me, I hate that I feel gulity

Its just that, today I have some heavy deadlines for my team that really can only be done today. My boss is useless and my last coworker was fired, I know I should just let my company figure it out but its tough to get over the mindset of its my responsibility to get things done. Im meeting them in the middle today, I let my boss know I'm getting the tasks done and am leaving the office at noon, I just wish I could have taken the full day.