At least she doesn't live with her, like in My Unrequited Love.
It's worth noting that in My Unrequited Love, Uta and Kaoru had a close relationship for many years before Kaoru married Reiichi, whereas Ogawa views the protagonist as a coworker and maybe a friend. Much of the drama in My Unrequited Love involves Uta trying to come to terms with her feelings and find out what, if any, place she has in Kaoru and Reiich's lives, whereas in Ogawa-san and I, it's most likely that Ogawa and the protagonist were never very close (at least not as much as the protagonist thought), hence why the former never told the latter about her marriage. Both stories do have the "unrequited love" aspect, but the execution seems quite different.