How do single mums balance it all?

I used to be a cracking employee, the reliable, high performing type who new the job inside out and smashed targets. These days I'm pretty shit and it's not for lack of trying. 

I also used to judge mums who didn't work but back then I wasn't a mum; I didn't understand what a bloody nightmare having a child was and I didn't know of the strain of finding and maintaining a work-life balance. I used to finish work, come home, watch endless episodes of Real Housewives, piss around on the internet and play with make-up. It's never about me anymore, it's always about Fred, and work and handling pressure and juggling hours and constantly trying to keep up with life. 

I've been a single mum for around four months now, without being disrespectful to Fred's dad I was pretty much single mum before; all the responsibility fell on me from the finances to Fred's care to holding down a stable job. Life hasn't changed much since he left aside from being able to cook the food I like and having more wardrobe space but finding that balance has become more complex. He lives over 200 miles away, the distance means he's not there at the drop of a hat to co-parent, he's not there to take on the struggles and release some of the burdens either financially or physically so I couldn't be anymore of a single parent if I tried. 

This wreaks havoc with trying to maintain a job and manage everything else (including not getting stressed so I don't have another stroke and be totally useless); I didn't anticipate how poorly kids get in childcare and how often. I thought I could have the carer and be a Mum and be some kind of super hero but a year into this rollercoaster I've very quickly learnt that it is in fact impossible to have all your shit together and whoever makes out it is anything other than a constant nightmare is a knobhead. Standard nursery and childcare policy is that if a child has a bout of sickness and diarrhoea, they're not allowed to return to the setting until 48 hours after it's stopped - this is to avoid spreading infection and because understandably, cleaning up the puke and shitty nappies of several grotty kids is impractical and fucking gross. I understand and appreciate why this policy is in place but I didn't anticipate how often kids get infected; my friend (a mother of four) advised me that until they're around three years old they're pretty much ill from October - March, I thought she was exaggerating...we're onto our second October and I can confirm that she was in fact telling the truth. 

Fred is on his third round of the shits in as many months, his stomach bugs are more regular than my periods which doesn't help when I'm trying to hold down a job and salvage a career in my absolute state of a life. Three stomach bugs in three months means that I've had three absences from work very quickly and followed by three instances of sickness for myself because Fred loves sharing his germs and my immune system is fucked. Whilst my employers are understanding, accommodating and the rest - I still feel a huge weight of guilt for constantly needing time off, I'm more than aware that I'm letting people down and I dread returning to work; I feel as though I have to walk in with my tail between my legs because I've been off again and somewhat frustratingly, aside from some wet poos Fred is as bright as a button. It's not as though he's on the sofa, poorly and needing my full attention meaning that I'm sitting here wishing I was at work and then feeling guilty for not wanting to be with him, it's a vicious cycle of constantly feeling as though I'm disappointing someone despite the fact that I'm trying my best. 

There is a case that I could work from home, if Fred is well in himself and doesn't need undivided attention I could focus my efforts on trying to work but any employer would be concerned at how much I could focus and how consistent I could be. All of the family I have are working themselves and have kids meaning that they can't take time off work to look after my child nor would they want to at the risk of infecting their own kids and needing further time off. I'm in a position where I am consistently off work, out of annual leave and looking having to take unpaid leave and be out of pocket. It's situations like this where I would be better off not working; I wouldn't have the childcare costs and disgustingly I would bring home the same amount of money in benefits than I would my monthly wage but in turn I'd be bored out of my mind and Fred would probably barely get poorly because he wouldn't be around other kids to get sick. 

How do working single mums cope? Is there a magical hack for handling the never-ending stomach bugs and holding a job down or am I right in thinking that it's a myth?