I have been in a similarish situation to you: my partner had cancer and had to go for chemotherapy. We live in a village, and the hospital is about 50km (30m-ish) from where we are. The chemo was over a few days every few weeks (I can’t recall now, it was a few years ago–he’s fine now!), and I wanted to be close to him to give that extra moral support, run errands and blah blah blah.
It was pretty tough. I didn’t close down my work (this was pre-Fiverr, mind, but I would do the same now) but what I did was that I made a very firm, set period of time to do work. Say 2 hours from x to y. Nothing was to disturb me from this unless it was my partner.
I know the biggest problem is focus, because you’re worrying about 1001 things and you really don’t care about some cheap client wanting a trivial revision. It’s OK to get a punchbag or scream. Once you’re done letting the emotion out, just sort of relax. For me it was closing my eyes and listening to classical music and thinking about good times. It’s also very therapeutic to talk to (mom/sufferer) about good times past. Laugh. It’ll put you back in a good mood, and no matter how sick your mom is, she wants you to do well in life and work.
It’s sometimes said that a serious illness takes down than the afflicted–it’s one good reason many underplay their own pains (“oh, I wouldn’t want x to worry about me too much”). It’s not modesty or politeness, it’s human nature. You can care and have your own life too. There is absolutely no reason to feel guilty about that. A sick person may lash out if they feel neglected (illness is lonely, after all), but remember that they feel shit and as any doctor will tell you, “if they’ve got the energy to complain, they’re alright!”–perhaps a little black, but from my own experience entirely true! As the old adage goes–it’s the quiet ones you should worry about. My point here is mainly that you need to be who you are through this whole process and not let it drag you down. Your Mom wants to see you being happy, cheerful and successful. Just one boast about how you nailed a $100 order will make her even happier than you can imagine.
I know it’s not much. Don’t fret too much about the Fiverr system. Use the tactics above (if you think they will work for you!) to complete your outstanding gigs and then go/stay on vacation so you can put your energy where you really want it to be.
Don’t forget to take care of yourself, too. Work should take a backburner here if you can afford it. If you can’t afford it, then you need to work out a good strategy that doesn’t stress you out too much. My best wishes to you both.