Bella Thorne Back With Age-Appropriate Boyfriend

Old flames are hard to extinguish -- especially after getting played by Scott Disick -- which might explain why Bella Thorne's glued to the hip of her ex, Gregg Sulkin, again.

Bella cheered on her ex-bf Thursday at his soccer match in L.A. The two have been spending a lot of time together since her trip to Cannes with Scott, which didn't end well.

Gregg's the better match ... he's 25, she's 19. Disick's 34.

Bella and Gregg dated for over a year before splitting last summer. Looks like another summer fling is in the cards.