I would like to say I have the absolute answer to this... but I don't. All I can tell you is from what I have learned and what I have yet to uncover. Love whether it be familial, a friendship, or romantic is always something we should be able to rely on. We should never be highly too dependent on any one of these, but we should also be open to accepting new forms of love into our lives. There will be days where one is better than the other and where one is meant to be a lesson while the other is meant to stay forever.
Love, is complicated. While it is easy to feel, it is not so easy to act on it. We may have someone we love, but will that person sacrifice what you are willing to sacrifice? This is where we then develop expectations of others that we simply cannot. We cannot control people, but we can have typical standards. It should be an equal weight of care on both parts and all relationships take work. Yes, a couple or friend can be truly happy, but they had some hiccups they had to overcome along the way. That is the way of the world.
These hiccups are mostly because people see things differently and value things differently. So when I say love should not hurt: this is not what I mean. Fights are normal and other inevitable things will occur however, love should not be draining. It should not strip you of who you are. It should not make you question your morals. It should not be something only you are sacrificing for. Love should be understanding. Love should be at least 50/50. It should definitely be filled with good memories. Above all, it should be filled with support. Love is there for the hard times and the good times. Love sees it all.
When you feel that way: you know it's right and unconditional.