How old is the battery? Has the car been driven mostly in the northern U.S. or
mostly in the southern U.S. since the current battery was installed? (Northern
U.S.: Batteries last longer.) Had many jumpstarts with this battery?

Got a voltmeter? If so, with the car off, what is the battery terminal voltage?
Now with the car running, turn on the headlights; what is the battery terminal
voltage reading?

Air filter, fuel filter, plugs, ignition wires, distributor cap and maybe rotor:
When changed last? All parts OEM cost around $130 total. If you don't do them
soon, they'll probably be due within a couple years at the latest, anyway. Good
investment.

Have you switched gas stations recently? Try a new gas station.

Add a bottle of Chevron Techron (~ $6) to your gas tank next time it's near
empty. Fill up.

Probably not as critical these days, but maybe try to keep the gas tank over
half-way full at all times, especially in the winter.