Since the last WooCommerce upgrade customers are not able to change their passwords. When I contacted Woo, this is what they said (below). But when I turn the plug-in off, the https never turns on, even at checkout.
Some of the aspects of the My Account page have been replaced with endpoints; in the case of a Lost Password page, it's an endpoint and not a shortcode, for instance:
You can see that it works if you use the URL above, but not when you just use http, which is what the 'Lost your password?' link is hard-coded to use on your site. This seems like another problem caused by the redirect issue you're having. I think at this point you should disable any HTTPS Redirect plugins and only use the Force Secure Checkout option in WooCommerce, as it seems to be causing more of a headache than just using WooCommerce built-in functionality.
I hope this clarifies the problem, and hopefully disabling that extra plugin resolves it. Please let me know if you need any more help.