Venus / Saturn and Moon / Saturn easy aspects.
Maybe the conjunction as well.I don't mention the hard aspects because they often lead to so much insecurity and fear concerning other people and the whole emotional / romantic sphere of life that they can lead to self-destructive behavior eg. cheating just to feel attractive and wanted or looking for other people outside the relationship for support and emotional reassurance in case of a conflict with the partner.
Ruler of the DSC in aspect to Saturn, maybe.
I'm not sure about Pluto and Neptune easy aspects - I suppose they can be quite positive and play out as devotion and faithfulness.
I think Venus conjunct Pluto is usually like that.