"So in the fading light I shut my eyes and kiss Gale to make up for all the kisses I've withheld, and because it doesn't matter anymore, and because I'm so desperately lonely I can't stand it.
Mockingjay, pg 198
"Take Peeta. Take me. Or even Finnick. I was starting to worry he had his eye on you, but he seems back on track now. I know he was desperate. That makes people do all kinds of crazy things."
Mockingjay, pg 200
Literally one page apart. Also,
"I'm so desperately lonely I can't stand it"
Gale just arrived. She's been away from him for two weeks and she is mourning Peeta. She's spent several hours with him by now and even the kissing isn't making her feel comfort. How can anyone say she has feelings for Gale? She's using making out as a means of escaping the pain she is in over losing Peeta. Her kissing him is once again about pain but this time it's her own.