This cusp business can be so tricky and confusing. Let's explore this:Could Moon in Libra on the 29th degree be focused more on learning to build/initiate interpersonal relationships that are worthwhile building rather than being blindly initiative(cardinal)?
The cardinal signs always creates a psychological "crisis" point which drives urgency(this especially when very close to 0 degrees Aries,Libra,Cap and Cancer).
So whilst the 29th degree of Libra is very far from 0 degrees of Libra, the first part of life could be about responding to the cardinal "crisis" nuance of this sign. Then later on one changes their tune and goes another direction.
Libra is about relating and having another to bounce off ideas on. So Libra often creates a crisis in relating i.e "I have to talk to someone. I have to find someone with whom I can share what I am thinking with in order to gain a perspective. I must. I must.I must " etc.
So when in the Moon's position, there is often quick initiating of relationships of an interpersonal nature. Or the search for "the one" who will fulfill emotional needs etc. This could be the search for a "best friend" or a romantic partner who will fulfill that role.
Does this lead to one initiating unfavourable emotional relationships or giving too much too soon in order for relationships(platonic or otherwise) to progress? Absolutely.
Does it happen that there is a point reached where if the "giving" is not reciprocated, they can feel "burdened" by relationships & feel like they have nothing more to "give" and people just "take", "take", "take"? Yes.
The point of no return(which the 29th degree actually symbolises) is when the Libra comes to refuse the "subjugation" of their own needs and initiates "divorce" on one hand.
Or the Libran comes to carefully select relationships that honor the agreement of reciprocation on the other hand (as Libra 29 is on the Virgo duad).
So this could mean being more specific(Virgo) about which relationships one pursues and refusing to entertain those that are not reciprocal or don't add value in ones life.
For those that one subsequently chooses, the native is fiercely devoted(Pluto conjunct). There is "above and beyond" loyalty and going all out to please the other party perhaps?
But this prudence in approach may still not absolve one from conflict(Virgo duad introduces so many specifications about "how" their connections "should" behave, that conflict is inevitable).
The added conjunction to Pluto may precipitate the conflict to a point of eventual separation. Or even the sudden severing of ties-either by the Moon in Libra person or the people involved with them.