Boy problem?

Okay so there's this boy I like. Him and I have been friends for a year I think and last year I went out with his best friend, who he refers to as his " brother " But his friend (who's name i dare not speak) broke up with me last month and now I'm thinking about hooking up with this guy (let's call him A)He just got dumped by his girlfiend and is in an awful mood. He keeps talking about how much he loved ( and still loves) her and it makes me feel guilty because My relationship with A's friend was the longest I've ever had. And I felt like I really loved him too. But I'm just ready to move on. The problem is that I'm afraid to ask A out because 1.)He's still mourning his exgirlfriend, and 2.) I don't want to seem like a lier, I always used to say how much I loved his friend and that nothing would ever change that. But now I wanna go out with him! I don't want him to think I'm a and/or that I lie when I say I love someone. I'm just ready to move on, I'm ready to love some one else