This seems like a pretty bad situation but can also work to your advantage once you are accustomed to it.
If you use Undo in Object mode, then you can use Redo before re-entering Edit mode to prevent the loss of what you've done.
There reason I say this can be a good thing is because you can bypass the maximum number of Undo's available to edit by entering Object mode then pressing Undo.
Also, this can save you a lot of Undo's in Edit mode if you know that you want to discard all the many small changes that you have recently made.
What is common to all DCC apps is the save button. Use it often and if you use Shift+Ctrl+S then press the + on the NUMPAD, you will have a saved version that has an increment which is one higher then the previous saved version so you will now have 2 .blends and the second will have a 1 at the end of the name. Do this again and you will have another with a 2 appended to the name.