Hi guys,
I decided to seek for your advice because I know I only got that one chance.
It's quite a complicated story I have for ya.
I had been in a relationship for a year and a half when I met this cute and kinda shy girl at the party. I didn't love my girlfriend at this point and I ended up talking with that girl all the time and kissing her. I'm not proud of it but who cares now.
The next day she texted me and we've been texting for the whole day. Only after that did I tell her I had a girlfriend. She wasn't mad at me at all, but she ordered me to tell my girlfriend the truth or - otherwise - she would do it. However, I convinced her that it's not such a good idea. Anyway, she told me she enjoyed talking to me and want to continue it anyway. So we stayed in touch and texted each other for days. My girlfriend even found out about her and I told her it's just a new friend of mine (I'm a dick). She was jealous anyway, no wonder why. That new girl asked if I want to meet and we did twice. We were just talking, nothing happened there. It is clear to me that she liked me but still she felt bad about me cheating.
A few days later we met at the houseparty thrown by our common friend. We sticked together, had fun and drunk some. For a moment, we ended up alone in a room. I couldn't help it, I went for a kiss, but somebody walked in and interrupted us. After that, she asked me what I was even thinking and that it can't be like this anymore. She told me I had to tell my girlfriend this time, finally.
I did. I told her right after my girlfriend randomly bumped into us cuddling in a city a few days later. That felt like a movie scene. I wasn't expecting that to happen. She caught us in public. I finally told her the truth. My girlfriend got histerical, started yelling and walked away. A moment later me and that girl had to depart because her bus arrived. We didn't even have much time to talk about what happened but she was shocked and confused.
Shortly after that I had to go abroad for a month. We stayed in touch with that girl but it wasn't the same. At the beginning it was quite ok, but then she started to be cold. She texted me and responded much less than before. It continued like that till I got back home from abroad, after a month.
Then there were like three conversations when she ended up not responding or hardly responding after a few messages. I sent her a longer text asking what's going on and telling her to be honest because I could clearly see something was wrong and I didn't like it like that. That's exactly what I texted to her.
She responded me that she likes me, but she feels a wall between us that's pushing her away.
I said 'Thanks for being honest, I just don't like running after somebody'.
I got a response that she can do nothing about it.

Since that we've had no contact for two weeks. Untill yesterday. I randomly asked her about some aspect of her life, sent her a photo of me and a friend of mine and we did a little smalltalking but - again - the conversation was dead after a while!
I want this girl but my current situation is shitty because we haven't seen each other for nearly two months and all I can do is text her on Facebook. After this time there is barely a bond between us and I fucked. Do you guys think there is still some possibility to fix this? If yes, then what move should I make now? It seems like a hard task because all that time made it stale.

During the time we hung out she clearly liked me, she was the one asking me out, but she felt wrong about it. After my girlfriend caught us, it's been cold. I can assume she rejects me on a logical level, but the problem is that some time passed and there is not much of an emotional bond there once was (we used to text each other day-long).
Needless to say my girlfriend is now my ex-girlfriend.

Forgive me my English, it's not my native language.