What Rich means by "compulsory heterosexuality" and "lesbian existence"

Rich, in regard to "compulsory heterosexuality", says, "It was written in part to challenge the erasure of lesbian existence from so much of scholarly feminist literature, an erasure which I felt (and feel) to be not just antilesbian but antifeminist in its consequences, and to distort the experience of the heterosexual women as well.  It was not written to widen divisions but to encourage heterosexual feminists to examine heterosexuality as a political institution which disempowers women--and to change it."  There are a lot more quotes, but to summarize, Rich says that "lesbian existence" has been erased from our culture...even documents, etc.  She is saying in this quote that the idea of "compulsory heterosexuality" was partly created to challenge that erasure from history.  She says that it was written ultimately to be overridden by women when they realize that it's actually disempowering them. 

In regard to "lesbian existence" Rich says these three things among others: "Lesbian existence suggests both the fact of the historical presence of lesbians and our continuing creation of the meaning of that existence.", "Lesbian existence comprises both the breaking of a taboo and the rejection of a compulsory way of life.", "I do not assume that mothering by women is a 'sufficient cause' of lesbian existence."  As for the first one, there IS  a history of "lesbian existence" as noted multiple times in the article, because they were punished (even by death sometimes) and their documents, etc. were destroyed.  There is still "lesbian existence" today because it's everywhere.  In the second quote she explains what makes up "lesbian existence".  She says that it comprises of 'the breaking of a taboo', which would be the fact that 2 women are together, and 'the rejection of a compulsory way of life', which means if I decided to be a lesbian I would be rejecting "compulsory heterosexuality" by not requiring my self to marry a man.  There was some discussion in the article regarding the possibility of lesbian existence generating from being mothered by a woman, but Rich in stating in the third quote that she doesn't agree with that.  And for that  matter, I don't either because that would imply every woman becomes a lesbian which is absurd because humans would no longer reproduce naturally.