Your only hope - both of you - is restoring to a backup. If you are using the "Rolling Autosave" feature, you should have more than one version of your save which you can try loading.
For example, if my save is "Amaroq", rolling autosave will create "AmaroqV2", "AmaroqV3", etc. I might be able to load AmaroqV2 - back in time a fortnight or so - if anything happens to my current save.
Of course, if all of them are corrupted, or, Dan, if you played your new game for several months, overwriting all of the autosaves .. then you've no chance.
I
strongly recommend that everybody turn "Rolling Autosave" on - unless you really are almost entirely out of disk space, its just
so heartbreaking to lose an FM save-game..