Jamie id be angry too. people are taking advantage of your good and kind nature and thats unfair. you have every right to be mad, frustrated, confused, upset. when you give SO much of yourself and get so little in return, it really bites.
Hang in there mate
Jamie, you are a good person and therefore want to help others. That is a very good quality. I do think that you should stop being the loan person for others. You need to be firm and tell them you cannot afford to give them anymore money because you need to take care of your own needs. I know this may be hard as you want to help but you come first and you need to be able to handle your expenses and be able to feed yourself. The others seem to be taking advantage of you. So please do get up the resolve to turn these people away. Especially if they are not going to pay you back. Your sister has no right to ask you for money and then go off on vacation. Sorry it's not working out with your lady friend. Sometimes we have to accept that which is not right for us. Take care.