From your initial summary of the situation, you come across as an intelligent, literate woman and my feeling is that yes you could do the job, it's only self-doubt that is holding you back. When I want to do something but am feeling out of my depth, I break it down and daft as it might seem, i pick up the phone and say 'yes' to whatever and don't think about the consequences. I f I do think I dither and talk my self out of it.
Splash has come up with a good idea about being able to split the job with someone else if you think that would help.
As for your Mum passing away, well all I can say is that when mine passed away, I spen 2 weeks felling miserable and then like you gave myself a good talking to and got on with things. It was the right approach for me, but not for eveyone. If it is the right way for you, I guess you would have made your mum very proud.
Good luck
-------------------- I have the talent of single-minded determination and foc....hey, look, dog!