Are you saying it doesn't remember your last used font when you Quit Photoshop gracefully and launch it again?
Try this experiment:
1. Choose the Text Tool, select whatever font you like, click in a document, and type something, and complete the tool.
2. Quit Photoshop; no need to save the document.
3. Launch Photoshop.
4. Choose the Text Tool. What fond is selected?
That is exactly what I am saying.
Well, for most folks gracefully closing Photoshop (opposed to having it crash) then opening it again later results in the same font you used last time being presented again next time you use the Text tool. This is true with many/most things.
Do you see similar behavior with other features - for example the last settings you used successfully with, say, Unsharp Mask being presented again next time? Or do they also revert to defaults every time you open Photoshop?
If you're losing your preferences and the memory of the last things you've done somehow your settings are either not being saved successfully, or are being reset every time you enter Photoshop.
What system are you running (Mac/PC)? What OS, specifically?