Honestly I think if you aren't completely over your crush and they are with someone else, it is normal to feel a bit of jealously/tension, which results in dislike or hatred towards them. If they are with someone else, it would be best to try and get over them. If you do, the fact that they are with someone else probably won't matter as much.
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F.A.I.L. is just the First Attempt in Life.....
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