<human>: Can you provide a brief rundown of the text in within 3 sentences?

Recently my brother and I were at a party and my girlfriend got kind of drunk and had a conversation with my brother. Basically she told him that she was going to tell me that she loved me soon. This is problematic because i don't really love her back. I care for her very much and want to stay in this relationship with her, but having been in love before i know that i do not feel this way about her. My brother, knowing how i feel, advised for her to wait for me to say it first. However i dont know if she will listen to him. So my question is; if she tells me she loves me, how do i respond? i can't really imagine saying anything back except i love you too, but i really dont want to lie to her. Any help would be greatly appreciated, thanks.
<bot>: I think my girlfriend is going to tell me she loves me soon, though i dont feel the same way and will have no idea how to respond if the time comes.