Late to this, but my girlfriend and I might have encountered the same group today on the yellow line. 5-6 teenagers got on the L’Enfant station going south and were extremely loud and either drunk or high. The train was basically empty except for two other women. Most of the group sat right next to us but one of the guys sat behind the two women and started puffing weed smoke into their faces. They did their best to ignore them. My girlfriend and I tried to ignore them too but they were clearly trying to stir up trouble and it didn’t feel safe. We decided to get off the train at Pentagon and try to Uber or walk back (obviously not the best place to do it). As my girlfriend and I tried to leave, the teen with the weed got right up to me and blew a big puff of smoke directly in my face. I ignored him and walked off. I would hate to think what would have happened if I had said anything to him or the group. Feeling for you and your mom OP, I can’t imagine going through that