chastity

 We know that both the brothers had different Gopis through the writings of the most prominent Vaishnava Acharyas and from the bonafide Vedic scriptures. Here are some citations from many available:

1. Śrīla Śrīdhara Svāmī states that the gopīs who enjoyed conjugal affairs with Śrī Balarāma during His visit to Gokula had not taken part in Śrī Kṛṣṇa's rāsa dance, being too young at the time. Śrīla Jīva Gosvāmī confirms this statement by quoting a phrase from the Bhāgavatam (10.15.8)—gopyo 'ntareṇa bhujayoḥ—which indicates that there are particular gopīs who act as Lord Balarāma's girlfriends. Furthermore, Jīva Gosvāmī states that during the Holī festivities celebrated when Kṛṣṇa killed Śaṅkhacūḍa, the gopīs Lord Balarāma enjoyed with were different from the ones Lord Kṛṣṇa enjoyed with. Śrīla Viśvanātha Cakravartī agrees with this explanation.
   
   >>> Shrimad Bhaagavatam 10.65.17
2. In his Laghu-toṣaṇī commentary, Śrī Jīva Gosvāmī writes: “The word gopīnāṁ in this verse refers to other gopīs, for the use of the word gopī does not always refer to Kṛṣṇa’s gopīs. If one says that both subject matters are the same—Kṛṣṇa enjoyed pastimes at night with the gopīs, and Baladeva also enjoyed pastimes at night with the gopīs—so there is no difference between Kṛṣṇa’s gopīs and Balarāma’s gopīs. In reply to this it may be said that no one should have such doubts, because the gopīs described in the previous rāsa pastimes are different from these gopīs. Therefore one should understand that Balarāma’s gopīs are different.
   
   >>> Śrī Caitanya-bhāgavata Ādi-khaṇḍa 1.25
3. While Balarāma was in that happy mood, He desired to enjoy the company of the gopīs in the water of the Yamunā. Therefore He called the Yamunā to come nearby. But the Yamunā neglected the order of Balarāmajī, considering Him intoxicated. Lord Balarāma became very much displeased at the Yamunā’s neglecting His order. He immediately wanted to scratch the land near the river with His plowshare. Lord Balarāma has two weapons, a plow and a club, from which He takes service when they are required. This time He wanted to bring the Yamunā by force, and He took the help of His plow. He wanted to punish the Yamunā because she did not come in obedience to His order. He addressed the Yamunā, ”You wretched river! You did not care for My order. Now I shall teach you a lesson! You did not come to Me voluntarily. Now with the help of My plow I shall force you to come. I shall divide you into hundreds of scattered streams!” When the Yamunā was threatened like this, she became greatly afraid of the power of Balarāma and immediately came in person, falling at His lotus feet and praying thus: ”My dear Balarāma, You are the most powerful personality…”
   
   >>> Krishna Book (Shrimad Bhaagavatam 10th Canto) 65: Lord Balarāma Visits Vṛndāvana

Hence, only one Gopi was shared by Lord Balarama and that was Mother Yamuna. But we must know that in the spiritual world the living entity can expand itself and so did Mother Yamuna, one form for Krishna and the other form for Balarama. Hence, both the Brothers relished the Raasa Dance with Mother Yamuna at different times.

Please remember that Krishna was about 11 & 1/2 and Balarama was about 12 & 1/2 years YOUNG when They left Vrindavan and these Gopis. This reminder is for us to understand that there is absolute chastity in Their relationships.

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