#2 Service to self is important and not necessarily “selfish”. It is reasonable and considerate to take care of yourself when you can. Doing so puts you in a position where you can better serve others and where others won’t have to serve you too much (e.g. if you’re self-sabotaging or self-destructive). But beware of falling into hyper-independence and closing yourself off to assistance that you are better with.
#3 Service to others is important and not necessarily “sacrificial”. You can put a suitable limit on how much you extend yourself and provide for others. Serving a bit is still better than not serving at all. How generous you can really be without betraying yourself or resenting it is for you to figure out. But you might find that, for the right causes and the right reasons, it is both relieving to others and fulfilling to you.