Usually cats are independent animals, but sometimes they can get excessively dependent, demanding and clingy.
A dependent cat will follow you everywhere, whining constantly to draw your attention.
Some breeds, like the siamese, seem to be more over-attached and clingy than others. If you spend most of your time outside perhaps it's not a good idea for you to have a siamese cat.
Try to keep your cat busy, giving him/her some toys and letting him/her leave home. There are benefits to let your cat go outside. If the surroundings allows it, don't hesitate, let the cat go, let him/her be more independent.
Signs of a clingy cat
Usually follows his/her owner everywhere, jumping on the owner's lap the minute he/she sits. These cats tend to keep ears in a vertical position.
One solution to draw the cat's attention away from you is to get the cat a feline companion, another cat.