Cakescakescakes - where did I go wrong !!! ???

I thought I'd do a kind deed today, in making a rich fruit cake for my uncle who recently lost his wife . He misses her cakes so much . Soaked fruit overnight in brandy , added flour (plain) butter, 5 free range eggs , dark brown sugar , spices , mixed peel, cherries .... didn't look 'cooked ' after 4.5 hours , so added a further 30 minutes ..... and this is the catastrophic result - one collapsed fruit cake ! It's my own Bake Off disaster !!! ha ha !
M