Parting from one's child was not in fact akin to losing a limb. Aelinor remembered that an old woman had once said something the like about the death of her son. She had claimed to miss his presence as one missed a limb, the phantom clinging to living flesh, continuing to smart and produce pain. The Queen could not agree to the description.
Losing one's child was a pain so intense she found herself wondering how her heart continued. There were many ways a child could die to their parent. Vhaella being taken away to be raised as the natural child of her brother was in effect the death of Aelinor's daughter and the birth of Rhaegel's child.
And there was nothing to be done. She could not claim Vhaella without condemning herself, Brynden and Rhaegel too. If the truth ever came out it would be the chopping block that awaited them. So Aelinor swallowed her tears and returned on her own to King's Landing. if the Seven had any pity of her they would give her daughter long life and good heath.