I don't disagree that there would be lots of women who would try to scold or drag them (back) into Labour, but that is a problem they would have to tackle.
There is more to the Left than the Labour Party.
I was careful not to specify any particular party but instead talked about Socialism and I did not have in mind that those hypothetical activists would be motivated by a desire to herd women towards Labour.
You are sounding a bit like Labour loyalists who tell us that if you are against the Tories, you only have one voting option!
What are the other options at the moment, not for Labour vs Tories but for "Labour-supporting or left-leaning women who have an epiphany about Labour and the Lib Dems."?
You could add other Left wing parties to that short-list.
However, if these women are "Labour-supporting" or "Communist Party-supporting", etc. then they would be obliged to leave those parties if they were members and wanted to set up or join another party.
If by "support" you just mean "who they would vote for" then how many more options would you like?
I am not suggesting that there should not be more options but bear in mind that the more options there then the more you are going to split the vote.
So one option would be ideal - but would that then put you in the position of "sounding a bit like Labour loyalists who tell us that if you are against the Tories, you only have one voting option!"?
If there are other women out there who want to have a go at setting up the Party that you envisage then, seriously, get together and have a shot at it. Nobody is stopping you 🤷♀️