Hi OP,
I'm a social worker, I don't have personal experience of what you're going through but I can give some advice about your general situation if that will provide any reassurance, I'm sorry you're in such a difficult position. Your backstory sounds absolutely horrendous and I'm so sorry you had to go through that, to be the victim of such abuse at any age is horrible but at such a young age and twice is incomprehensible.
You have to understand though that no matter how sympathetic a professional might be to the reasons why you drink, and the causes of your mental ill health, that the standard of 'good enough care' that social services are required to assess doesn't change. By that i mean a child's right to be safe, to have an adult around them who is responsible, who can react appropriately in an emergency, be loving, caring and emotionally available. No matter what the cause, if you are drunk and/or suicidal and the children are in your sole care that isn't safe and it would be a frightening position for a child to be in. You sound like you're already aware of that happening at times so I'm not going to labour the point, I know its not something you want for your children.
So what next? Well, many parents have situations where children aren't safe for many reasons. A social workers job is about trying to work with you to reduce the risks whilst keeping the family together. Its unusual to order a parent to leave the family home unless there's a direct threat to a child (a common one would be a parent who is violent either to the child or the other parent for example, where there's a high chance of violence repeating).
What is more likely and what it might help you to start considering now, is what support you can draw on to protect your children. If you're drinking a lot of the time, you need someone else to be around to help care for the children - can your partner or any other family support? If your drinking and your feelings around suicide fluctuate, are you able to identify when you're going downhill? Or can people around you identify that? Do you have strategies in place (kids going to friends, a supportive mental health team etc?)
I've worked with parents with fluctuating conditions (eg bipolar) to develop safety plans where the parent is able to identify when things are starting to go off kilter and know who and when to get others involved for support, including who the children will go to when there's hospital stays involved etc, who will take them to school, all of those sort of things can help mitigate the risk. The best plans involve the children themselves so they know whats going to happen (obviously what info is shared is age dependent, but young children can be included if its done right) Safety plans dont' have to be as intensive as to require others to do childcare, but can include lots of little things that make a difference eg one person doing a school run, access to an after school club, a child having a sleepover at their friends. Anything that adds up to taking the pressure off enough that you can get through and the impact on the children is minimised.
NB i didn't want to come at you with a list of services as that's something that as professionals we tend to do too quickly (can be a bit one size fits all) but if you drink to cope with flashbacks i just wondered if you've ever had any kind of support to deal with those symptoms?