I took a fair amount of MDMA in my late teens/early twenties. Mostly in nightclubs and music festivals. It was cool at the time (great memories and the music 100% was better).
In my late twenties (after 5+ years without MDMA), my partner and I decided to roll after getting some MDMA off the dark web. We went to a bar, which was my past go-to, and had an OK night. We left pretty early and went home.
When we got home, we had 100mg left each and decided to roll in the peace of our house. We both dropped a cap and spent the next 6 hours having very deep conversations and just caressing each other (I especially enjoyed touching her hair).
We didn't have any major issues in our relationship leading up to that night, but we did have a bit of friction over our future plans. After that one night, our relationship was at least 30% more pleasant and we both felt significantly closer to each other.
We still have a great relationship 2 years later. Obviously, the MDMA isn't the only factor, but it helped to dramatically strengthen our feelings towards each other.
One downside was sex. She was very in the mood and I was unable to perform on MDMA.
YMMV.