I know saying it out loud sometimes makes things too real for us, but your partner is checking in with you and you have to be honest with him and yourself. If your symptoms get worse or you develop PPD or may be harder for both of you to realize and you could be delaying getting better. Please talk with your partner and let him know where you're struggling. I hope you start to feel better soon.
Agree with both comments above. Be honest with your partner and maybe discuss the therapy option with them. And don’t let it make you feel guilty. You’re not failing anyone! You have just done an enormous thing giving birth: you’ve put your mind and body through extreme changes and experiences, had to make quite a few sacrifices on the way too. And all that for 9 months. After birth you had (and still have) to be there for your baby, waking through nights, feeding etc. leaving very little space for yourself. So it’s ok not to be ok!! Your body is still fighting to get itself back. Your mind too. And it’s normal to need help. 🫂 just be honest and open about where you are and how you feel. It’s the first step in working to change all of that
Have you tried writing it down. I find that gets thoughts out of my head and makes it a bit easier. Then you could choose whether to share those with hubby. Maybe even write in there why you didn't want to tell him?
Have you considered therapy? Sometimes when I don't want to unload on my husband or friends/family, therapists are super helpful. They have online apps & options so no pressure to leave the house. My doc also made sure pp I was getting out to do something for myself at least 1x a week. This advice did help me.