When to give up

After talking with the guys on the man weekend about girls, i'm no longer sure what to think. we were talking about when we (guys) should move on from a girl. Hearing the other guys talk about stories of persistence and how it has paid off. . . now i dunno if i should give up.. part of me says yes, but at the same time i definitely dont want to. that brings into question whether thats what i should be doing or is that just me being desperate. i'm sure it's probably the latter, but i'd prefer not to think so negatively . i guess i'll pray about it and hope for a clear answer.