You’re right that you need help. What you’re feeling and doing to your relationship isn’t healthy or normal. The problem stems from your self esteem. If you were more confident that you were going to be okay with or without your boyfriend, then you wouldn’t need to make up incidents to cause his jealousy and then his expressions of how much he wants you. You’re basically manipulating him and trying to control his feelings because you’re afraid of losing him – or just his attention.
My guess is that this is a trait you inherited or learned from family, because when you mention that your family keeps “constantly reminding you” that he loves you, what you may be hearing is that they wan to make sure you hold on to him. This is an unusual message for family to give a 17 year old girl.
The reality I’d like you to see is that you’re going to be fine with or without him, and in fact the more independent you are, the happier and more intimate you’ll be in your relationship with him or any boyfriend you have.
I know this is going to seem incredibly difficult, but in order to get over your fear of losing him while he’s on holiday, you’re going to have to really focus on yourself in a healthy way. Stay busy. See friends. Go to movies, shop, cook, study, visit family, exercise, clean your closet – do what you need to do be okay while he’s gone. If you don’t learn to do this, you’re going to crash and burn the relationship you’re in now, as well as future relationships. So take your own question, and this answer, seriously.
I hope that helps! 🙂