Home alone

I had a baby 6 weeks ago. Ive been dealing with postnatal depression sjnce. The first 5 weeks my husband was hone with me so that it was manageble. Now i am home alone all day again and its so bad. I spiral in very bad thoughts and the only reason i even get out of bed is my baby. I do not know how i can fix this. I will have to get used to being alone...but i dont know how.