Fellow girlies :) is this a reason to leave my man? should i be worried?

my boyfriend of 6 months seems very much in love with me, he texts me constantly and has cried hysterically over our relationship in the past. hes in the army and tells me how his friends go out every week cheating on their girlfriends. today i found one of my friend's friends has just split up with her boyfriend... turns out he was also in the army, at the same base, doing the exact same job! she was telling me how all the men at the base are cheats, and i said 'surely there are some exceptions' but she laughed implying i'm naive, and of course all the men are cheats. from my experience of these guys the men ARE all cheats and my boyfriend himself admits this, but says i can trust me and he loves me with all his heart (he was crying when i told him this tonight, and hes not the type to show his feelings or sensitivity) ive been cheated on in the past, so am I just being paranoid, or should I actually be worried? please no insults :)