Vrinda & Tulsi were different characters altogether, as were Jalandhar and Shankhchuda, even though their stories seem to have been conflated in several places.
Reading the link originally provided by Minakshi, Vrinda was not Jalandhar's shield, but Tulsi was Shankhchuda's shield. As per that posted account, Parvati was angry @ Jalandhar for trying to seduce her in Mahadev's guise, and to get back @ him, asked VIshnu to play the same trick on Vrinda. In other words, it was not something Vishnu did to erode Jalandhar's defenses. Vrinda's curse on Vishnu was just that his wife would be deceitfully abducted, and that he would be wandering about the forest looking for her. She did not curse Vishnu that he'd be turned to stone.
And yeah, Jalandhar wasn't enemy of Indra due to any Matsyakanya - the real reason was partly shown in DkDM. Jalandhar saw the headless Rahu, and Bhrigu explained to him why Rahu was beheaded. Following that, Jalandhar delivered an ultimatum to Indra to surrender everything that had been mined in the samudra manthan, and after Indra refused, Jalandhar defeated him in war. Vishnu refused to kill Jalandhar on Lakshmi's request - shown accurately in DkDM - and so it fell upon Narada to instigate Jalandhar against Mahadev.
In the Shankhchuda/Tulsi case, the story was slightly different. There, Shankhchuda had defeated Indra and conquered his kingdom. Here, Mahadev ordered Shankhchuda to restore to the devas their kingdom, and Shankhchuda refused, inviting Mahadev to win it by force, if he could. Now, here, Shankhchuda did have his wife's pativrata tapasya as his shield. In this account too, Parvati instigates Vishnu to violate Tulsi. Now, here, Parvati had no reason to instigate this as she arguably had in Vrinda's case, but the other reason - that it was necessary to violate Tulsi to break her husband's defenses - was actually true in this case. So in both the accounts, the rationale for Vishnu violating the women was different, but there.
Tulsi's curse on Vishnu was different. Unlike Vrinda, she cursed Vishnu that he'd turn into a stone - which is the saligram.
Vishnu's reactions to the end of both Vrinda & Tulsi was bizarre, to say in the least. In Vrinda's case, after she cremated herself, he took her ashes 🤢, smeared them on his body and wandered about aimlessly. The devas, concerned at this, approached Shiva to break Vishnu's obsession w/ Vrinda, who referred them to Parvati. Parvati, Lakshmi & Saraswati scattered some seeds on Vrinda's pyre, out of which 3 plants - tulsi, amla & malti emerged.
In Tulsi's case, unlike Vrinda, she did not die, but kept crying inconsolably. Vishnu meditated on Shiva, who appeared and 'blessed' Tulsi that she would be the beloved of Vishnu.
There is nothing in the story I read above about Vrinda & Tulsi being the same person. The story of Jalandhar & Shankhchuda have some parallels (both conquered the devas) but different in most respects.
Edited by .Vrish. - 12 years ago