I blame myself too as my partner said he couldn’t live with someone who was so hysterical over lockdown
If he wasn't someone who would support you emotionally then he's not a 'partner' worth having, or even a friend. A lot of people find the lockdown hard, and you weren't being irrational to worry about your work.
It's early days so you're bound to feel awful. Time, music, letting off steam to people, maybe medication or therapy (which you could get over the phone) could help.
Actually I think medication would be good, as your mental health was already not at its best. You could talk to the doctor over the phone.
Either way, these things take time, all you have to do is wait it out. I know you said you don't feel like it, but if you can go out for some walks- being outside can take you out of yourself a little.
Eat well- maybe deliveries/takeaways, or anything that can tempt you and you usually enjoy.
Get any practical stuff sorted out like benefits etc if you're eligible. Others can help you fill in forms etc if you don't feel up to it.
Best wishes. xxxxx