You do feel overwhelmed at first - that feeling doesn't last.
It doesn't totally go there are waves, but you WILL get through this.
Sleep when and where you can (I couldn't bear to sleep in the marital bed at first, after a few uncomfortable nights on the sofa with just a throw I accepted I wasn't ready and moved proper pillows and a duvet downstairs so I was more comfortable)
If eating is a struggle liquid foods - soup, slim fast or similar (lots of added nutrients), smoothies
Drink plenty staying hydrated will help you feel better BUT avoid caffeine and alcohol as they'll make you jittery and depressed
See gp if necessary temp ad's or even stronger meds can help
Take the support offered by others, don't be a martyr. I spent HOURS on the phone to a lovely relative i'd not previously been that close to and a friend who had emigrated to aus was great for chatting online (this was pre social media days it was all msn messenger back then! No voip either) in the wee hours as it was daytime at hers
A neighbour I barely knew lent me money (no easy electronic transfers then and he left me totally skint with a toddler to feed! Bastard!) which I repaid when my parents transferred some money to me via post office
I had wrongly assumed Ssafa would be on his side then I had to see them about something else and the lady in there was amazing and gave me loads of really good advice! She also advocated for me on some matters which made it he had to take responsibility for some things he REALLY didn't want to (too outing to say here but feel free to pm)
Even my TORY Mp helped us avoid homelessness! Yep ex would have let me and our child become HOMELESS if it had been up to him
He is NOT your friend now