Very common. Generally feel loads worse before you start to feel better.
Just tell yourself, one day at a time. Get through today, then take tomorrow as it comes. You will begin to feel better in a few days. Try to keep busy, and distract yourself.
I know it feels like checking out of life would be the best option for you right now, but that is just a chemical imbalance in your brain, and not rational.
Your ds would not be better off without you. He would miss you every day, and constantly wonder why you didn't love him enough to stay around and watch him grow up.
That is not the legacy you want to leave.
My xh committed suicide when ds1 was 5. Despite having 3 lots of counselling, he still has no self belief, he always picks friends and gf's who are 'damaged' in some way. As though he can 'fix' them (and in that way redraw the past). He hates been by himself, and would rather be with the wrong person than alone.
I am doing all I can to boost his self esteem, to value himself, and to not always put everyone else before himself. To do what he wants to do, to not be such a pushover.
I don't know for certain, but I suspect these are all the legacy of him feeling 'abandoned' by his df.
And the ripples of my xh's suicide still have an effect over a decade later.
I'm sure it takes a lot to kill yourself, in terms of mental anguish, and the thought processes of getting to that place. I have been there myself, but thank god, not quite rock bottom enough to end it. Having been through the bombshell of my ex, I just couldn't do that to anyone else. No matter how bad I have felt.
You are on the path to recovery, but it won't be easy at first. The first few days are the hardest.
And in a few years you will be able to look back and feel a sense of pride that you managed to hang in there, and have been around to watch your son grow.