I was a serial quitter for several years. I'd post at a previous forum that some members here were also a part of, so some of them may remember how I'd fail repeatedly. One of them (not here in this forum) told me I wasn't serious about quitting if I was not just sticking with it. That wasn't true. It was embarrassing to be in the cycle of getting excited about quitting, stubbing out what I expected was the last cigarette, set my signature ticker with the quit date, and post daily pledges and relapse. I didn't always post my attempts at quits, but many of them.
Whey your why-quit becomes stronger than your why-smoke, you'll make it happen. Your why-reason should be something to feel excited about, strong enough to give you a kick of dopamine or adrenalin, a sense of power, and maybe guilt isn't doing that.
I wanted to be sure I could survive Covid, so I quit just as it hit the USA in 2020. The vision of being on a mechanical ventilator in a hospital was a chilling one for me. I was on one once, and it was not pleasant to return to consciousness and find a tube down my throat, feeling immobilized, hearing beeps and hisses, disoriented, alarmed.
Don't give up on yourself. You can do this.