Narkissos....In case you were replying to me, my comment was directed to the OP. I of course agree with you.
possible-san....You raise an interesting question of whether the beloved disciple of v. 27 was construed as member of the group mentioned in v. 25. Oun in v. 26 is little more than a connecting particle and simply links the situation in v. 26 with that in v. 25. The more interesting question is why the beloved disciple is not mentioned in v. 25 if 'he' is not part of the group of women in v. 25. I think the author is trying to depict the three women as a group at the cross and the beloved disciple as near to them (and hence outside the group of women). The women in v. 25 "stood near the cross" (eistékeisan para tó stauró); their location takes the cross as its point of reference. The beloved disciple's location in v. 26 however appears to be relative to the women, or Mary of Nazareth specifically: "Jesus saw his mother and the disciple whom he loved standing nearby (parestóta)". What the English translation here fails to convey is that parestóta is a singular masculine participle and thus grammatically agrees with the case and gender of mathétés "disciple". If the author was construing the disciple and Mary of Nazareth as together standing near him, the plural form of the participle would probably have been used. So the sense is not that "Jesus saw [(his mother and the disciple) standing nearby] but "Jesus saw his mother and [(the disciple) standing nearby]". Since the plural is not used, the sense is probably that the disciple is standing near the group of women and Mary specifically. The translation by Beasley-Murray (Word Biblical Commentary) tries to convey this sense: "Jesus therefore, on seeing his mother and the disciple whom he loved standing near her ...".
This consideration alone is ambiguous and not decisive. What specifically rules out the identification of the beloved disciple with Mary Magdalene is the verbal exchange in v. 26-27: "When Jesus saw his mother there, and the disciple whom he loved standing nearby, he said to his mother, 'Woman, look at your son (ide ho huios sou)', and to the disciple, 'Look at your mother'. From that time on, this disciple took her into his home". Jesus is not referring to himself as Mary's son; he is telling Mary that the beloved disciple is now her son just as the disciple now has her as his mother. The two statements are reciprocal and address the mutual relationship that now begins between the two of them, which could be paraphrased as follows: "Woman, take a look at your son who now takes care of you. Son, take a look at your mother to be cared for by you" (compare the similar formula in Tobit 7:11, "From now on you are her brother and she is your sister"). So the beloved disciple is quite explicitly male.
Mary Magdalene and the beloved disciple are again distinguished in 20:1-2: "It was very early on the first day of the week and still dark, when Mary Magdalene came to the tomb. She saw that the stone had been moved away from the tomb and came running to Simon Peter (pros Simóna Petron) and to the other disciple (pros ton allon mathétén), the one whom Jesus loved". Mary is not running to herself; she is not the beloved disciple at least with the text as we have it.
With respect to the identification of the beloved disciple with Lazarus, the internal evidence is quite weighty. Until we get to ch. 11, the author had not yet referred to Jesus having personal affection to a specific (male or female) disciple. Then all of a sudden, within this chapter, Lazarus is introduced and we have three specific references to Jesus loving him:
11:3: "The sisters sent this message to Jesus: 'Lord, the one you love (hon philei) is ill".
11:5: "Jesus loved (égapa) Martha and her sister and Lazarus".
11:35-36: "Jesus wept, and the Jews said, 'See how much he loved him (pós ephilei auton)!' "
Lazarus is last mentioned in ch. 12 and it is at this juncture when the references to "the disciple whom Jesus loved" commence (John 13:23, 18:15-16, 19:26, 20:2, 21:7, 20). The only explicit antecedents for these references are the statements in ch. 11 about Lazarus, and none of the references to the beloved disciple precede ch. 11. The first reference to the beloved disciple in 13:23 describes him as eating at the table with Jesus while "reclining on Jesus' chest" (anakeimenos en tó kolpó tou Iésou), and the only prior reference to a disciple reclining at the table with Jesus was Lazarus in 12:2: "There they made him a supper and Martha served but Lazarus was one of them who reclined with him (anakeimenón sun autó)". Lazarus is not the only one who reclines (anakeimai) at the table with Jesus but he is the only one specifically named and who also is the only one who is specifically described as personally loved by Jesus. Lazarus and the beloved disciple are also uniquely mentioned as known to the chief priests (12:10, 18:15-16). And the reference to the rumor about the beloved disciple not dying in ch. 21 takes on added significance if the beloved disciple is the one Jesus had raised from the dead — would he have to die a second time before the parousia? Within the context of the gospel, the rumor makes intuitive sense (Jesus is the "resurrection and the life", so why would Lazarus have to die again?), even if it is presented by the author of the appendix as a misunderstanding of Jesus' words in 21:22. But why is the author so cryptic and indirect in referring to Lazarus as the "disciple whom Jesus loved" in ch. 13-20? The answer might depend on how 19:35 is interpreted. If, and this is a big if, the author is here making an indirect authorial claim of being the beloved disciple who was there at the cross, then the indirectness is a distancing literary device for the sake of modesty (cf. Paul's obsessive concern about boasting throughout 2 Corinthians and the very indirect way he related his visionary experience in ch. 12).
I do not mean to say that there is any certain identification of the beloved disciple in John. The matter has been subject to so much debate and controversy over the years. I am only saying that the identification with Lazarus is the best one I have seen and the one that imo is best supported by internal evidence.