What does one do after committing blasphemous acts?

Salam,

Hope everyone is doing well. I've been having a horrible time, for a long time. I really sought out support and change from Allah, and did all the advised ibadah. I asked to at the very least gain some mental ease over the severe hardship i've been facing for years. I stopped praying or making duaa recently out of anger/sadness, and I've thought and said really horrible things about Allah SWT. I'd rather not repeat them, but very very bad things. I'm almost thirty and I have never had this opinion of Allah until now. Anyway, I'm not sure what to do, because I still need help from Allah and I still need to worship Allah for the sake of my akhira. How do I ask for forgiveness. The problem is that I don't really feel guilt. Be it that I have horrible iman or what, I don't really regret anything wrong that I do - I just try not to do it again. For example, if I commit haram, I don't really regret doing it but I make sure to never do it again because it's haram - if that makes sense.

How do I ask for forgiveness when I still am upset with Allah. I can't really make myself not be upset or have guilt or regret. That's not how the brain works. Do I just continue to worship Allah and continue to make duaa, maybe explain why my mind is where it's at and how I know it's technically disrespectful. I know Allah says he is kind, hates to see us sad, and does what's best for us - but my brain is refusing to comply or believe that. I've been through a lot, it's taken a lot for me to get to this.

Allah doesn't punish us for our thoughts, so as long as I worship him and don't say blasphemous things out loud, am I okay?