Why am I so sad.

Before I was pregant or even with my current boyfriend I had struggled with depression and anxiety. I cut every day. Once I left my last relationship it all went away. Other than the occasional sad day or thought. I am now 2 years clean of cutting. Recently (I am 9 weeks pregnant) I have been feeling so alone, and cutting is all that's on my mind. My boyfriend helps in anyway he can, but my brain keeps telling me bullshit. My boyfriend isn't the cause of any of this. He is there anytime he can be, but I dont know why I am so depressed. I know it might just be the hormones, but it feels different. Can depression worsen during pregnancy?