MY girlfriend Frigid?

Right ive been going out with my girlfriend for about 4 monthes and she says she loves me ever night but when it comes to in person she only kisses me she like can i get in ur bed on the phone and sytuff but when it comes to it, it dont happen i love her so much and we both trust each over but i want to show that i love her by doing more any idears on how if she is frigid x