Jacqui Lambie is difficult to work with and "disrespectful" according to former members of the senator's party whose votes prop up Tasmania's minority Liberal government.
Now-independent MPs Miriam Beswick and Rebekah Pentland were booted from the Jacqui Lambie Network on Saturday for being too "cosy" with the Liberals.
The pair, elected to state parliament in March with the network, have said they would continue providing supply and confidence to the Liberals but were working on a revised deal.
Ms Beswick said the pair's relationship with Senator Lambie had been "getting difficult".
The senator accused the duo of failing to hold infrastructure minister Michael Ferguson to account over delays and cost blowouts for two new Bass Strait ferries.
Mr Ferguson on Monday sensationally dropped the portfolio to put an end to "commentary" around the project.
Ms Pentland said Senator Lambie had not consulted with herself or Ms Beswick when announcing positions on state issues.
"The way things rolled over the last week is an example of that," Ms Pentland told reporters on Monday.
"We probably needed a little bit more autonomy and respect as politicians to make those choices.
"We didn't feel like we were respected.
"The relationship was unworkable and it's fair to say it was irretrievable and we needed to make that step to properly part ways."
The pair are not the first elected MPs to depart the network. Senator Tammy Tyrrell quit in March, saying Senator Lambie was not happy with her performance.
Ms Pentland said she was looking for more freedom in a tinkered deal with the Liberals and to be treated the same as other state independents.
The Liberals hold just 14 of 35 lower-house seats and must work with a cross bench now consisting of five independents and remaining Jacqui Lambie Network MP Andrew Jenner.
The Liberals have been heavily criticised over their handling of the delivery of the larger Spirit of Tasmania vessels, slated to begin arriving in late 2024.
It was revealed the ships, already substantially delayed, will not be able to operate at full capacity for about a year because an upgraded wharf won't be ready.
The boats also need a yet-to-be-costed temporary berth, while government-owned operator TT-Line had to pay an extra $81 million to the builder to keep the project on track.
Mr Ferguson, also the deputy premier and treasurer, took a shot at TT-Line when announcing he was dropping infrastructure responsibilities.
"In the absence of the company owning up to this profoundly disappointing situation, as the (minister), I will," he said.
"The ongoing commentary concerning the project is proving an unnecessary distraction."
In mid-August, TT-Line chair Michael Grainger pledged to "set the record straight" about the reasons for delays, before being sacked by the government.
Mr Ferguson said he could not afford the government to be distracted ahead of preparations for the 2024/25 budget, to be delivered on September 12.
Senator Lambie, who has been contacted for further comment, welcomed Mr Ferguson's decision to step aside and called for him to resign as treasurer.
"All ministers have a responsibility to the people of Tasmania to carry out their duties to the highest standard," she said.
"Where that obligation can't be met, they must be moved on.
"Unfortunately, Mr Ferguson proved to be incompetent."
Premier Jeremy Rockliff will take over the infrastructure portfolio.