Did Tamar marry a third time, and if so whom?

Question

B'reishit 38:26 says:

וַיַּכֵּר יְהוּדָה וַיֹּאמֶר צָדְקָה מִמֶּנִּי כִּי עַל כֵּן לֹא נְתַתִּיהָ לְשֵׁלָה בְנִי וְלֹא יָסַף עוֹד לְדַעְתָּהּ:

Then Judah recognized [them], and he said, "She is right, [it is] from me, because I did not give her to my son Shelah." But he no longer continued to be intimate with her.

Rashi says on this verse:

But he no longer continued: Heb. וְלֹא-יָסַף. Some say: he did not continue [to know her] (Targum Onkelos), and others say: he did not cease (Sotah 10b). (A similar instance is found in connection with Eldad and Medad (Num. 11:25), [where the verse reads:] וְלֹא יָסָפוּ, they did not continue, which the Targum renders: וְלֹא פָסְקוּ, they did not cease).

If Yehudah did not cease, does this mean he married Tamar? If he did not continue (which is the translation I've always seen until now), then did he finally give her his third son? Or was that unnecessary now that children were produced? If so, did she go off and marry someone else entirely, or did she remain unmarried?

(I checked Sotah 10b but didn't find any further enlightenment there.)

Answer 1

Siftei Chachamim elaborates on both possibilities listed in this comment of Rashi:

יש אומרים לא הוסיף ויש אומרים לא פסק. ה"פ מ"ד לא הוסיף סבר דעתו של יהודה לא היה שיבא אליה אלא כדי להקים זרע על שם המת וכיון שקיים לא בא עליה עוד. ומ"ד לא פסק סבר כיון שראה יהודה שמתאוותה להוליד בנים ממנו והיה כוונתה לש"ש לכך לא פסק מלדעת:‏

Some say he did not continue whereas others say he did not cease. Some say Yehudah did not continue since his only reason for being with her would be to establish seed in the name of the deceased. As he had done this, he ceased from relations [although Halachically she was his wife]. And some say he did not cease since he saw she yearned to have children from him. Her intentions were pure, so he continued being with her.

^{Translation and parenthetical insertion by Metsudah.}

So, at least the way this translation takes it, Tamar remained married to Yehuda, either way. Also either way, she had already borne children - Yehuda's - in her deceased husband's name, so she had no further requirement to marry Yehuda's sons.