unprofitable servant

I work for my mother, She's a rich exec, who sold 1 business and is dabbling in building another. Because I had a baby and the need to get out of the house, I offered her my talents before offering them to the wider community. She snatched me up to be her assistant.

In her employment I have done/been  many things:
1. A personal shopper
2. An event organizer
3.  A caterer
4. A cook/ kitchen prep
5. Accounting assistant
6. Genealogist
7. Researcher, scientific, social and misc.
8. Pet sitter
9. Writer, technical and other
10. Gardener, indoor and out.
11. Talk writer

I have help set up many things, websites, plant water filters, slide shows, events.

But  mostly, I bring her grandbaby over.

However much I do for her and "earn. (she pays me enough to keep from looking for any other employment)" She always manages to turn around and just for fun buy me things, that I, with out her could never afford.

Overall, I feel like an unprofitable servant. I can never giver her more then she gives me, (Besides financial, I also get all sorts of sanity saving and emotional support, encouragement to continue pursuance of my dreams and just plain intellectual stimulation.) Add on that the normal mothering she has given me (like life and raising to adulthood, college ...ect). Gee, I guess I can never repay her for all. But I can keep trying.