If you liked the 3D Material manga, the Anime-Planet community thinks you'd like:
Nana K. is a hopeless romantic who is co-dependent on everyone around her and falls in love at first sight with any and all men, even married ones; Nana O. is a wannabe rock star who has had to break up with the love of her life so that she can find her own path as a singer. As Nana K. boards a train to Tokyo, she longs to finally be with her beloved boyfriend Shouji; as Nana O. boards the same train to Tokyo, she plans to live her dream with only the guitar on her back. The two meet by chance both on the train and in the city - ultimately choosing to live together - and though they are opposites in every way the girls quickly become close friends. Together, Nana and Nana will learn the bittersweet truth about love, loss, and the growth that comes because of it.
Nana has a very similar feel to the first of two stories in 3D Material - a girl struggles with love and betrayal. Nana is much better in all ways but I still think fans of one should give the other a try. Just keep in mind that the second story in 3D Material is nothing like the first, and is rather throwaway.
Iwaya Sumire is a highly-educated, well-respected and young journalist at a major newspaper - though her social success can't stop her boyfriend of five years from dumping her for a less-educated woman. One day, as she's fuming over her lost relationship, Iwaya comes across a young man in desperate need for food. On a whim, she takes him to her home and feeds him, deciding to let him stay in exchange for becoming her "pet." With him at her side, Iwaya takes on love and life.
Both are centered around a female protagonist that really seems emotionally distant and somewhat cold. The manga are mostly about their growth and relationships, disfunctional as they may be.