Don't flirt with a girl when you don't really mean anything you say.Don't text a girl all day long when you're actually texting more than one girl. Don't go out on a date with a girl when you'll just take abother girl out the next day. Don't tell her you're thinking about her when she isn't the only girl on your mind. Don't tell her you miss her when you wouldn't care if you had never seen her again. Don't tell her you love her when you would just love to get in her pants.Don't make her feel like she's special when there are other girls who are getting the same treatment from you. Don't make her promises you know you aren't able to keep. Don't make her believe you care about her when she is just an another girl to you. By doing these things you get a girl's hopes up and you give her expectations and because that happens, thr disappointment hits her so hard and now she is emotionally damaged.