Doesn't look as if she married in Cheltenham. Freebmd has two Mary Ann Excell marriages in Gloucestershire between 1872 and 1911
Mary Ann E Excell 1878 to either John Graham or George Richards in Bristol
Mary Ann Excell 1880 to William Hooper in Dursley. This looks like a double wedding as the other couple are Edwin Excell and Elizabeth Hooper. Unless Mary Ann had a brother Edwin, this probably wasn't her.