I've had a few loves over the years, though not many relationships. At first, I thought that love was losing myself in another person, but I've learned through the experience of feeling regard for another that loving (as I feel it, at least), is a combination of knowing oneself and accepting it, so one can know another and accept them.
There have been moments where an unrequited love has felt like dying, and others where it has felt painful but almost like waking up out of a dream and seeing the other person clearly for the first time, and yourself as well, because love is an outgrowth of self-knowledge. It's liberating to feel enough caring towards someone that what you really want between you and another are truths of self, even if those truths don't lead to happily ever after. It's still the truth of who you both are, and that in itself is lasting and extremely meaningful.
Granted, I am not in relationship now, nor have I been for some years. It's very taxing for me and the toll it takes feels like too much at present. But one hopes that enough inner swirling will settle that there will be bandwidth for another.
In the meantime, however, there is still oneself to explore and accept.