"Love" seems to me to be quite an ambiguous word in English ... for example, depending on who's saying it, "I love you" might mean "You give me what I need", or, "I give you what you need."
Brahmaviharas
One of the recommendations about "being loving" is the doctrine of the Brahma-viharas ... for example, this essay introduces them by saying,
These four attitudes are said to be excellent or sublime because they are the right or ideal way of conduct towards living beings (sattesu samma patipatti). They provide, in fact, the answer to all situations arising from social contact. They are the great removers of tension, the great peace-makers in social conflict, and the great healers of wounds suffered in the struggle of existence. They level social barriers, build harmonious communities, awaken slumbering magnanimity long forgotten, revive joy and hope long abandoned, and promote human brotherhood against the forces of egotism.
The Brahma-viharas are incompatible with a hating state of mind ...
I think they're all worth considering. If your partner becomes more enlightened then that would be occasion for mudita, for example.
The recommendation that these are right attitudes isn't specific to people who are "in a relationship" but, given they're for "all situations", that includes someone with whom you have a relationship.
Traditional responsibilities
The suttas include advice for married couples, including a definition of responsibilities ... the duties of the husband and the duties of a wife.
I'm not sure it's sensible (I doubt it's sensible) to have these expectations of your partner if they're unwilling (i.e. if you don't see things from the same perspective).
To the extent that people do have needs, expectations, and duties, I think they're supposed to have different kinds of needs: e.g. what children need (and what your duties towards them are), is different from what your wife needs, your employees need, your parents need, and so on.
I think it's easy in modern society for a couple to try (and fail) to be all things to each other.
Not
Notwithstanding the Brahmaviharas, it seems to me that many Buddhist qualities or ideals are defined as a "not": for example, being "harmless" (Avihimsā, also translated as "friendliness or "absence of cruelty"); or, "attachment" (desire, clinging) is seen as a cause of suffering, so conversely non-attachment is a good thing.
Similarly I think that being selfish (which I think includes having views such as "I need this" and "I need that", and "I need you" and "I need you to do this and that for me") is going to be counter-productive to the aim of reducing suffering.
Expectations
There's a bit of advice in this answer about what to look for in a marriage partner.
If I may say so I think I might interpret the subject of "needs" a little differently than Dhammadhatu does. One of the foundational virtues is "generosity" (i.e. giving), which might be seen as almost the opposite of being "needy".
I expect young children (infants) to be "needy", I kind of expect adults to be the opposite of needy, i.e. generous and independent.
Specifically
You said that the two of you have "opposite needs".
My theory is that you would do better if you were less needy, or at least more independent at satisfying your own needs.
I actually see each of those needs in isolation (rather than being in opposition to each other).
One believes they need space to heal and find themselves
I'm not sure there is a "self" to find (so this "need" might be either doomed to failure, or at least badly expressed).
What more likely I think is that this one has a current view-of-self which they don't like (a view that's self-imposed and/or which their partner is trying to impose on them).
I suspect they might not "find themselves" but do want to escape from a view-of-self which they find constraining. For example if they're being told "You don't meet my needs", that's disparaging (their partner might do better to, instead, encourage what they're good at).
the other needs understanding that comes through meaningful communication
Three theoretical problems I foresee with this include:
- Asking for "understanding" is asking for an overcoming of confusion, which is difficult ... not impossible but maybe a central problem or "root" of all other problems
- Any communication might be seen as unsatisfactory (unsatisfactoriness might be a characteristic of almost anything), so saying "I need communication" as implying that "My need could be satisfied by communication" might not be true
- It puts of burden (a demand) on the partner: "You must communicate with me, otherwise my need will not be satisfied." I think that (perhaps paradoxically) a "loving" relationship might be better when the partners are more independent and less demanding.