A good timeline of the changes in her graph would be useful. Yours is 20 years old - the other you posted? I don't like the first but see what others say.
Here is a PSA certified example that seems the same hand as the "Mary" example but later ("L" "R" etc):
The lady said she didn't recall the exact date, but thought it was around 1980 or 81, her husband managed stores during that time and the band came to the store to promote the album, so it would appear that she used to have less fancy, more typical handwriting - simple J's, no fancy crossing of the T's etc.