IDK anymore feel like giving up

My co-parent is refusing a true 50/50 custody split. Currently, I have our son for 8 out of 14 days in a two-week period, while she has him for 6. I’ve pointed out several times that this schedule shortens her time, but she insists it’s a 50/50 plan and the best arrangement. Over time, the discrepancy becomes significant.

I’ve proposed two solutions to make parenting time closer to 50/50, but she rejects both. She claims she needs Saturdays off for work, and I’ve offered to watch our son on weekends while she works, but she still says no.

Now, she wants to claim our son on taxes every year, offering not to ask for child support if I agree. I have four kids (three from a previous marriage, who are with me 5-6 days a week), a mortgage, car payments, food expenses, and no state assistance because I make too much. I’ve even stopped taking my diabetic medication because I can’t afford it, and it’s only a matter of time before I end up in the hospital. She knows my financial situation but insists on her way.

She recently quit her day job, moved in with her mother rent-free (though I’m sure she’ll claim otherwise), and earns about $1,500 a month from weekend house cleaning. She also collects EBT and smokes marijuana during the day, all while telling me she misses and loves me—despite leaving me twice. I’m done with the relationship, but these issues remain. I try to be a good co parent, last week she was sick during her time, I took our son no questions asked. She needs supplies, I make sure my son doesn't go without. I coach his basketball team, I'm very involved in his school going to meetings etc...I've tried to be an active parent.

I make about $6,000 a month (with a second job) but still live paycheck to paycheck. I’m worried about the wage disparity and the possibility of getting screwed in court. As bad as it sounds, I’ve even thought about leaving town and telling both moms to figure it out themselves—but I know I could never actually do that.

Honestly, I’m just venting, but I’m open to any advice. I feel like quitting.

This is obviously a burner account.

UPDATE: First of all I really appreciate everyone that took the time out of their day to read and comment, good bad, ugly IDC thank you for doing that.

Went to the gym after this vent and kicked my ass, got this negative energy out of me and Im not gonna give up. I also told my STBX that im done trying to get her to spend more time with her kid. I'll gladly take the extra time and I'll try to figure my finances out on my own. the whole dependent situation I still dont know what I'll do, if that is literally the only thing stopping this from going to trial then maybe its in my best interest to just give it up. At the end of the day I dont lose any time with my kids and thats all that really matters to me.

Thanks again! I'll go back to lurking on reddit.