It depends on the religion you’re speaking of. Judaism is a religion developed in the concept of “being unlike others”. Christianity is a religion that is “similar to Judaism” and “influenced heavily by Greek and Roman culture/s.”
As with any religious law, it is important to note the context in which it was created and understand what possible function it may have served.
In traditional Judaism, you are supposed to procreate (preferably having at least one boy and one girl, but anyway) and it is biologically impossible for two men to do that. Reform and most Conservative synagogues are accepting of same-sex relationships when the two members are both Jewish or at least willing to live a Jewish life and raise their children Jewish.
If you consider that male ejaculation has potential sperm and females are born with a certain number of eggs, then, yeah, it would make sense that two women engaging in sexual activities may be seen as less of a grievance than two men spilling seed. shrug Women and men were segregated throughout their lives, with women often spending a lot of time in close quarters together. Close female relationships are noted throughout Jewish history.
Usually Jewish law (where applicable) applies to both men and women. Since there are certain biological and socioeconomic differences between men and women, the expectations vary slightly. For example, women are exempted from certain prayers because it is expected that they are busy child-rearing.
Some rabbis and scholars I’ve heard say that since there would be little community consequence of two women (as opposed to two men who could be independent, not procreating, and not supporting women and children) having a frolic, it may not have been as big as a deal. It doesn’t mean it was considered okay. This could be one reason why lesbian relationships don’t even get an honorable mention in the Tenakh. What may be considered “a little unnatural” is not always “a sin against nature”. (:
There is also the question of males being “unnaturally” dominated by other males. I looked at Wiki since I can’t toss you any of my books right now and it gives some insight:
All that being said, women are not going to get a pass when it comes to same sex relationships in modern Jewish communities that do not condone male same sex relationships.
*Please note my quotes for expressions. I’m answering the OP the best way I can. I’m not sharing my personal viewpoint here.