Fed up

To all the genuine good hearted people who always give, give, give and ends up with the short end of the stick all the time. How do y’all manage to stay positive all the time. I always give more in any relationship (boyfriend, family, and friend wise) I always get told that I need to be more selfish because I do tend to get taken for granted because of my big heart. I know I’ll get my blessing for it but I try to stay strong and positive when I get did dirty. I’m a forgive able person but never forget anything either but I just can’t seem to not be so generous when it comes to helping others out if they need it (stranger or not). Any advice on how to put myself first without feeling guilty about being a lil selfish towards others. I’m kind of fed up with some people not valuing me in return. It hurts that people you genuinely care about be the main ones who undervalue you the most when they know you’re the most solid person they ever came across. I know somebody can relate so any tips, advice, or encouragement on how to go about this would be helpful. Thanks in advance! 😊