OK, first of all, how do you spend your days? From the lack of information about life outside the home, I'm guessing you aren't working? How old is your daughter and is she with you all day?
Isolation is terrible for our sense of self. Working, volunteering, getting out and about every day somehow is vastly better than staying homer, no matter how much you might want to cocoon. It does take time to build connections, make friends, etc, but getting started is a great step.
An example from my past - I started taking the 2yo to a nearby toddler group, and after 2 months joined as a volunteer. I got to know other parents that was and made some good friends. I also started going to an exercise class in the hopes the stories about exercise and good mental health were true. (They are, but it takes a while). After several onths there, I got to know a lot of the regulars and we started going out for a cuppa after the class, and a whole new supportive group of friends was born. We WhatsApp several times a week.
I also started writing out my feelings of hurt andn insecurity rather than unloading them on one person. Then I'd do something else for an hour or two, then read them afresh pretending is was a letter from someone I knew, and how I'd respond to that person.
We're often kinder and more supportive to our acquaintances than we are to ourselves. That step back helped me recognise the skewed mindset I'd got into.
It was connections and habits like those that helped me dig my way out of the hole I'd got stuck in. I started to see what others did - not a miserable, nervous needy person with nothing but a husband and child to give her value, but someone outgoing, helpful, funny, compassionate, and of intrinsic worth.
It's hard to take those first steps when you feel so far away from being confident. I wish you the very best of luck. Ask your GP about CBT or other counselling.