Let me get you a cup of tea. 
I remember exactly this time and that was without all the lockdown shite.
I speak to you from the other side with kids aged 8 and 10. Life is a joy. I have hobbies, wonderful friends, great job and no crying baby.
When youngest DS was 8 months I found no joy in anything. I just kept wondering "when does this get easier......"
Then I went back to work and everything was easier and better and I appreciated my children, my time and my life much more.
Please don't worry about things that haven't happened. It won't be easy but you will find a way to make things work and if you simply can't, people are more understanding than not. My employer has always got my back and I am lucky but that's also because I put a hell of a lot in and it comes full circle.
At my worst times, it was other mums who got me through it. Not by actions but with sympathy and recognition and hearing all the shit they too were dealing with.
Please do something nice for yourself whatever that may be. A cake, a run, a chat with a friend, a non rainy walk.
The sun will shine for you I promise you that. Just be kind to yourself and get through each day without worrying about next week, or next month.
Hand hold. We've got you OP.