Its very hard to move on from someone that belittles your mind into thinking there mad about you when they don’t. She was obviously head over heels for him. Longest relationship and all that . It’s easier said then done to “get over it”or “move on”. I’d say the constant posting of the new bird has her head up her hole. I’d say every jack and sally are sending her screenshots daily too . I was with a lad for 8 years , and went through the same - it’s easier said then done. Your head gets messed up on so many levels.
I don’t believe she’ll go back, she’s just hurting , which is part of the healing process.