The singer was set to appear at the Emmy Awards in Los Angeles on 17 September with her fiance Pete Davidson but pulled out following the death of her ex-partner, rapper Mac Miller, who died from a suspected overdose.
On Thursday, Grande tweeted: “ur angels in my life. it’s just been a tough month. i’m trying to get my work done and get back to normal and it’s hard and i’m human and tired. sorry i let u in or worried u. i shouldn’t have tweeted. i kno better.”
She added: “Can i pls have one okay day. just one. pls.”
Fans of the 25-year-old were quick to respond with words of reassurance, with one tweeting: “I’m so sorry for your loss… Everything will be okay.”
Grande followed up her tweets by thanking fans, writing: “ty for loving me sm i do not deserve it.”
Earlier this month, Grande announced she would be taking “much needed time to heal and mend” following “events of the past couple of years”.
In an interview with Vogue earlier this year, she discussed her battle with anxiety and post-traumatic stress disorder following the suicide bomb attack at her concert at the Manchester Arena.
She said: “It’s hard to talk about because so many people have suffered such severe, tremendous loss.
“But, yeah, it’s a real thing. I know those families and my fans, and everyone there experienced a tremendous amount of it as well.
“Time is the biggest thing. I feel like I shouldn’t even be talking about my own experience – like I shouldn’t even say anything.”