My H has been in MLC at least 3 years.
At first he was definately low energy, and just sat in front of his computer getting lost in his own depressed thoughts.
As he started to express his feelings, he seemed to gain more energy, and his behaviour changed. He started to see OW, and wanted to live by himself (but was clinging at the same time, because he didn't want to go). He was full of contradictions and confusion.
He left (at my suggestion, because he said he wanted to go and I needed boundaries) several times. Each time he went, he made excuses to stay in touch, to come back.
Finally, he came back, and was more connected, but still had the idea that he needed to be by himself. He's still not out of MLC, still lost and confused, but now back to being low energy, but less depressed than before.