There maybe several reasons that cause her jealousy but here are a few common ones that could cause the rivalry.

Job Jump

This is when you get ahead in your career, land a fabulous job, and get a pay rise or a promotion. She will probably congratulate you and tell you that she is happy for you without meaning it.

If you are having a little gathering to celebrate then she will probably trumpet her own achievements and try and get the focus of everyone's attention on her instead of you. She may even tell a few people that you didn't deserve the promotion and that you got it because of whatever reason.

Not a Team Player

If the two of you are working together on the same team, then comparisons may be made between both of you. If you are praised over her for your work, the way you dress and the fact that you are more popular than her are reasons enough to get her to be jealous of you.

Matters of the Heart

If the two of you are in love with the same man and he gives you the attention over her, then that is another reason she might be jealous of you. She will want the love and attention showered over her instead of you.

Husband Money-Bags

You two have talked about having a dream wedding with the dream man over and over. If you do land up marrying a man who is wealthy and end up living out your dream, then it could be reason for your friend to turn foe.

She will want the status and privilege that you have married into and hold that against you. Remember, her aspiring for the same things are okay but when that turns into jealousy then the behaviour is uncalled for.

Dr. Dayal Mirchandani says, "If a friend is acting jealous then you can do your bit by not talking your success to her and in front of her. Talking to her about her problem with you will not work because people who are envious would deny it. So talking to her could make it worsen the situation because to her it would seem like you are pointing out a flaw in her."

Here are Five Friends Every Woman Must Have. Read on to find out why.