Medical/Dental expenses - who foots the bill?

I pay the family premium. My kids currently range from 20 - 29 and are at various stages of launch/failure to launch.

When my D, who is now 27, graduated, she was a NYC teacher for one year and had her own coverage. Then she left teaching and got a fellowship. It provided basic health care coverage, but I put her back on my plan. My employer also keeps them on dental till 26 and allows COBRA till 29. When D got a new job, I kept her on my coverage for dental and paid the COBRA when she turned 26. She then decided that she wanted the better dental plan (the one I don’t even have for the rest of us) so she paid the difference between the original COBRA, which I was also paying for my oldest son. She also paid her co-pays. She is domestically partnered with her bf and went onto his dental plan when he started working for Google. Before the bf worked for Google, he was self-employed and he went onto her insurance the day after she turned 26 and graduated from my health plan, which was the day they partnered.
My oldest son went onto employer health insurance (USPS) when he turned 26 but stayed on my dental until he turned 29. I paid the premium, which was less than $20 monthly. At first, I paid the co-pays, but when D went off my dental, I told son he had to pay his.
The other boys are all under 26 and I pay everything. The middle 2 are unemployed college dropouts. The older of the 2 has “issues” and will probably go on Medicaid when he turns 26 but the younger is looking for work. He has an inflated sense of what he should command in the work place, given his lack of work experience, and refuses to work retail, so it’s been hard. I can’t force him, I refused to work retail myself but I had office skills. The youngest will graduate college in May and I expect him to get employment. I will keep him on my health insurance and dental as needed, while I am still working.
They are all on my phone plan and I actually get a nice discount from Verizon due to oldest son’s employment with the Feds. The 2 oldest now buy their own phones. I provide low level phones for the others. I pay all car insurance but they are all (except college kid) expected to pay for their own gas. I give them the EZPass when they travel, but I expect reimbursement. It’s usually son 3 who drives on group trips and he collects money from his friends to pay me back for the tolls. I provide food but if they choose to eat out, it’s on them unless I am treating for a family occasion. I don’t pay for social activities.

Reading the responses here makes me realize how badly I am enabling my kids. I want to sell my large home and downsize but H refuses because the boys all still live here. I truly feel that I failed them because they have no shame at taking money from me.