If you are feeling suicidal one month before marriage it is only going to get worse when you are locked in. Call it off, seek a strong counseling support system to help you navigate through what seems unmanageable. People have success stories of moving though this. You can too. Please be encouraged and refocus your life so you want to live it for yourself and your child. No person should ever make you question that! The world is too big and beautiful, with many nice surprises if you position yourself in faith, do the healthy right thing, and expect them.

OP are you still out there? How are you?

OP, if you don't feel like calling a suicide hotline there is a suicide text line: 741741

Text it now, they are standing by to help you. 741741

You don't feel this way yet but I can assure you this is a moment in time that will pass, you will feel better and joyful again but you will have to work at it. You can do it with support.

Text 741741 now.

Op, you say you want to marry this man to keep your family together. But how will it keep your family together if it makes you kill yourself? Don't marry this person. Your dd will be much better off.

OP. you are not thinking straight which is part of suicide thoughts. Why would your boyfriend get 50% custody of your DD when you aren't even married ? No need to answer because it doesn't make sense. But that's how clinical depression works. Please call your doctor.
I have been where you are. I struggled hard for a few years to stay alive instead of dying. That time is over now. It seems like a bad dream and why ? What was I thinking ? Those thoughts are gone now thanks to medication then. It seems like something that happened to another person not the sensible person I am today. There is help. Hard as it is to believe this can go in the past and seem long ago and far away. Call your doctor. You will see. Don't do it.