My experience is rather the opposite of what you write. My 12th house Virgo Moon has always been the most difficult placement in my chart. My emotional nature is very restrained, almost to the point of repression. Yet I feel very vulnerable towards other people... I absorb and feel their emotions much stronger than my own. I can't remember the last time I got angry, sad or experienced any other strong emotion that was all my own. I cry because someone else is crying and I feel their sadness, not because of my own emotions. This absorbtion of feelings, that I definitely attribute to my Moon in 12th, is why I also blame this position for my other absorbing traits as well.
You are right about this for blaming your Moon.. Sensing and absorbing others' emotions. But I think your Moon being in Virgo and the opposite house of what Virgo rules makes it even more difficult.
My Moon aspects both Mercury and Neptune (by sextile and trine), Moon is in a house ruled by Neptune and a sign ruled by Mercury, Mercury is in a sign ruled by the Moon, Neptune is in a house ruled by Mercury... There are so many connections between them, so I'll admit that it makes for a very complicated picture and I can't rule out that the Mercury-Neptune opposition influences my tendency to assimilate other people. But yes, for the most part I put the blame on my Moon, the trine to Neptune only increasing the intuitive qualities already present. Wherever these absorbing traits come from though, Pluto is probably a helpful grounding force. Pluto not only trines Mercury, it also sextiles both Moon and Neptune.
Here is the part I disagree for two reasons.
One is that I have met many Piscean in some way Moons (including myself) And they do have good intuition and absorbing their environment's moods and emotions.
However none of them has the tendency to adopt others' people ways of speaking, habits etc.
But the opposite is true for people who have no Neptunian energy at all except of their Mercury (like my mom and aunt) and they have this habit of adopting maybe unconsciously all the stuff you said.
Second reason is that it doesn't make sense to blame a trine and a sextile for giving negative results, especially when there are hard aspects/placements who are stronger than trines and sextiles. Neptune trine Moon is a beautiful asoect to have, your problem seems to be that your Moon a. is in Virgo (not of the best signs for Moon to be) and b. it is in the exact opposite house of the one that is Virgo's natural house which is the 6th H. It's natural for your Virgo Moon to feel uncomfortable in there.
My biggest caveat though is that I have a hard time seeing Neptune as such a negative force. My experience with Neptune is overall so overwhelmingly positive. If Neptune is confusion and passivity then that has definitely been secondary to all the positives I've gained from it, such as creativity, inspiration, imagination, intuition, compassion, artistic talent... Those Neptunian traits mesh perfectly well with my Cancer Mercury. Neptune also affords me some strong rose-colored glasses that have so far only made my life easier and helped me have a positive outlook on life.
It's not a bad thing seeing Neptune as a positive energy. Also the negative traits we were reffering too do not really affect the native per se unless there is confusion of what's real and what's not or bad memory, it just drives other crazy after getting to know them lol.
My friend has Cancer Mercury opposition Neptune too but a Cap Moon. I think I talked about her in my previous replies as an example. She has these traits but she was not aware of them as you are about them. It took a few of people pointing out to her. My mom innthe otherside isn't even aware of it at all even though she is a bit more than 50yo.