Can someone help me with a translation?

[Julieta]

Hi guys,
I'm writing because I'd need some help translating a couple of sentences. I'd be really grateful if you could give them a look.

"どうして平気でいられるの？私のことなんか、放っておいても平気だっていうことじゃないの？"
This is a girl talking to a boy. I think she's asking him why he's ignoring her, but I'm not sure.

"電話くれるって、言ったじゃない。嘘つきなんだから。"
The same girl's speaking. I think this means "You told me you would call me. You're a liar", but I'm confused by the usage of んだから and くれる: shouldn't it be あげる?

何よりも会うことが大切なのに、会って、お互いの温もりを確かめあうことが必要なのに、「元気？」「まあね 」というやりとりだけでは、何も伝わるはずがないではないかと言いたかった。
Something like "She wanted to tell him that there was nothing more important than meet up and make sure of each other emotions, but with a simple exchange of "Hey, how are you?" "As usual" (on the phone), nothing could be transmitted.", but I really can't understand why のに is used.

(sorry for the awkward English :sorry

Thanks a lot for your help!

 

[Toritoribe]

"どうして平気でいられるの？私のことなんか、放っておいても平気だっていうことじゃないの？"
This is a girl talking to a boy. I think she's asking him why he's ignoring her, but I'm not sure.

She is asking why he is staying calm, and presumes that his calmness shows he is unconcerned with her.

"電話くれるって、言ったじゃない。嘘つきなんだから。"
The same girl's speaking. I think this means "You told me you would call me. You're a liar", but I'm confused by the usage of んだから and くれる: shouldn't it be あげる?

～（な）んだから performs as a kind of sentence final particle. It's used for conclusion here.

電話してあげる is a direct quotation 'You said "I'll call you"', whereas 電話くれる is an indirect quotation 'You said you call me'.

何よりも会うことが大切なのに、会って、お互いの温も りを確かめあうことが必要なのに、「元気？」「まあね 」というやりとりだけでは、何も伝わるはずがないでは ないかと言いたかった。
Something like "She wanted to tell him that there was nothing more important than meet up and make sure of each other emotions, but with a simple exchange of "Hey, how are you?" "As usual" (on the phone), nothing could be transmitted.", but I really can't understand why のに is used.

温もりを確かめあう more likely refers to physical contact.

お互いの温もりを確かめあうことが必要なのに、それをしないで「元気？」「まあね 」というやりとりだけでは･･･

 

[Julieta]

Thanks a lot for your answer, now I got it!