OP, it's not impossible, but I didn't find it easy at times! I'm a single parent with 2 DC. I work FT as a nurse. When the DC were younger, it was bloody hard: childcare hours didn't correspond with my shift start/finish times, and I was juggling a now XH who was a bloody nightmare. Luckily though, when XH pissed off, I managed to negotiate FT hours, that DID correspond with childcare hours: I was allowed to work those hours from when XH pissed off (I don't get any help from him), to when my youngest started secondary school. However...my kids are NT, have good health and have no disabilities to speak of. They go to mainstream schools, and were able to attend childcare settings without issue. My DPs both died when the kids were younger so I didn't really have anyone to help out regularly (friends with kids and myself would buddy up and help each other, as would my DB and I). I know for fact that as a single parent, I've had it a LOT easier than many!!
I'm (very) lucky because I've had a good education and qualifications. I've worked for the same place for many many years, so was a known entity there with a proven work track record. Therefore they were very understanding when the shit hit the fan with XH, and they allowed the variation in work times etc - hens teeth in my line of work, but that made a huge difference (so always worth asking about flexible work patterns). On the flip side, my employers have a staff member who is now able to be flexible, and will never forget just how much kindness and support was shown to me during some very bleak times in my life. I now am able to pay that forward with doing whatever I can to help the ward. I was also the breadwinner before XH left, so no worries about me having to do any "return to practice" type things, as I kept my registration etc current. I can't imagine how difficult it must be for single parents with kids who do have disabilities and cannot attend mainstream settings....or those trying to find work after so long out of paid employment...or those without suitable qualifications. I do feel guilt that I couldn't stay at home with my DC when they were little, and I feel guilt that my DC were/are like latchkey kids...and - like other single parents - I play a lot of catch up with housework/family time etc when I'm not working!! But I have to work, and so needs must.
Are you able to update your qualifications and experience in the meantime? Start researching what courses might be available or if volunteering is possible? Perhaps for the future look at a school or child care setting where you can use your previous work experience (although I appreciate that might not be possible with your carer commitments). Or maybe PT WFH/remote working (I don't know how common these jobs are!)? Or PT in a local hospital or care setting? I think UC can top up if you don't earn enough.