Without blame, without guilt, without regret, try to accept the condition for what it is.
I've had a number of medical conditions and incidents -- getting diagnosed with type 1 diabetes (which helped lead me to Buddhism), surviving a near-fatal car accident while crossing the road some years into my practice (couldn't walk or use my arm for a few months, what awful pain! thankfully -- nothing permanent), getting COVID a few times, and all other kinds of maladies.
IMO -- If the body has to let you know that it's hurting, that's not "wrong" or "bad," it is what it is. If you have to cry, let yourself. If you feel yourself needing more care or support, it's not wrong to acknowledge that or accept sympathy from those who care about you :) Compassion for yourself matters, too. Trying to bury those emotions and pretend they're not there won't help you help yourself in the long term. Buddhism doesn't teach compassion without reason!
What gives me strength in the face of pain and disabilities -- reminding myself that I'm not my disease, that I'm not my body, that I'm not my weakness, that I'm not my pain, and that it will all pass in time. Trying to ground myself in equanimity/upekkha also helps me tolerate the dukkha and rise above it all.
In terms of making peace with what's happened to you, don't just limit yourself to Theravadin teachings -- try reading Stoic texts or teachings from other religions and see what tools you can take from them.
It's our fate to fall ill, to suffer, to grow weak, to grow old. We can't escape it with good or bad karma. But skillful attitudes and practices can help us endure it, even if we still can't completely overcome the dukkha. Every time I've felt frustration arising in me for my dis-abilities, my training helps me distance my mind from the feelings and emotions just a bit -- and I've been able to feel some gratitude that the illness can serve as a teacher for me, giving me a chance to reflect and accept this world and this body for what they are.
Forgiving yourself and centering on metta is also good, too. As other commenters have said, you don't know for sure if the dukkha is "your fault." Even if it is, to some degree -- eg you smoked a pack or two of cigarettes a day and got lung problems, or maybe something in a past life did lead to this state of affairs -- if you can try to let go and forgive yourself, and resolve to live better in the future, and find ways to live well with the situation, despite the situation -- that's the way.
Metta, friend...