I am so sorry to read how overwhelmed you are, truly. While I haven't been through the same traumatic experiences you have, I have suffered from depression, and know how hard it is to find a reason to keep going & be positive. So first of all, good for you to recognize that you are in a difficult place & to reach out for help.
Second, realize that taking steps towards feeling better is going to take time. Nothing you do is going to allow you to wake up tomorrow all of a sudden wanting to go to work and having an easy time taking care of your children. It will be a step-by-step process, and you may not realize things are getting better. So, I would encourage you to journal, weekly (or daily if it helps) so that you can look back & see how far you've come.
Find out if your HR department has an employee assistance program. Some larger companies do - you can contact them privately for assistance with many things, including depression, and get a start at opening up with someone, and help with referrals to continuing care.
Depending on the coverage through your insurance, I would also suggest making an appointment with a psychologist. It sounds like in the past, medication was a significant factor in helping you to take control of yourself and move forward, but I think the opportunity to also sit down with someone and talk about past events and current problems is a necessity to help you overcome your feelings.
If you haven't done that before, I will say up front, it is not easy. And sometimes it takes a session or two before you are comfortable with the therapist, and sometimes it takes a couple therapists before you find one that you really "click" with. But don't let those attempts scare you off.
You mention depression & anxiety - the depression makes it hard to want to move forward to making things better, and the anxiety will freeze you from taking the steps once you decide to do something. Recognize that, and fight the urge to just run & hide.
I am hopeful that you have a close friend or family member you can confide in, who can encourage you and support you. Reach out to them, share what you did with me, even if it is just to show them what you wrote. Ask them if they can be there for you in some way, either to watch your kids when you have an appointment, or to check in with you weekly to give you positive encouragement and keep you focused.
If you don't have assistance through HR, and don't have coverage for therapy sessions, reach out to the community help line www.211.org for assistance in finding what you need in your area.
And if you just need someone to talk to, send me a message. T.