Bichons are known for being very needy. The little white furball will follow you around the house and insist on being as close to you as possible. They do not like to be separated for whatever reason or whatever duration and will often throw a fit if they feel they are not getting the attention they so desperately crave.
To understand the reason for this behavior, you have to appreciate their highly affectionate temperament that these dogs tend to have.
Bichons love to cuddle and play and hang out with their owners. It is how they show love and how they receive it. So if they follow you around everywhere and seem to want more attention than is reasonable it is because they are trying to bond with you. A little accommodation here will go a long way.
They are also not very independent. While Bichon Frises can be left alone, they hate it and will often sulk and whine all day long until you come back. Again, this is more about emotional attachment than it is about their inability to take care of themselves.
For this, you just have to train them and be patient. Eventually, they will learn the need to let you go because they will understand that you always come back.
Finally, Bichon Frises tend to be needy as a result of their psychological predisposition to anxiety issues. They are very timid and are therefore easily traumatized by anything from loud noises to harsh treatment.
Bichons are also vulnerable to separation anxiety due to the early removal from their litters. In these cases, a calming supplement like hemp, melatonin, or essential oils plus a little bit of patience will do the trick.