Solo MMR, I've given up, I play probably 0-3 matches a week. Mostly end up with players afk or disconnected in team, but I'm getting things done.
Party MMR is lot better, I got a party of 3, we go carry, offlaner, support pick and sometimes the other 2 in team fails but we pull it through.
My party MMR is ~2k while Average team is ~3k. My solo is now at ~1.5k.
If frustration builds up, watch SingSing lose matches. His reactions are hilarious but teaches how handle with non-compliant team mates. He does his work even though the team fails so has no regrets.
Update:
So I was playing party MMR and this happened.
Match 1974912547 - Overview - DOTABUFF - Dota 2 Stats
This was the pick order:
Zeus
Slardar
LS
BS
Riki
LS took easy lane, Slardar went bot, for some reason unknown Zeus went bot and Riki asked for mid. I asked for offlane with slardar but was refused by Zeus.
So, this game I played BS support. Courier, wards, items, I think I did a good job. While Zeus remembered my mother and sister particularly, I played my role and we won.
Probably, I've been reported but I think we wouldn't have won if no one played support. We would be a team with 5 carries with zero vision and survivability.
Interestingly, I was read a sub thread on reddit where someone had commented "I'll play support but I must get my Aghanim's and Blink." Slardar and Zeus could played support easily, but Zeus "must get his Aghanim's and Blink" and he went on to get refreshers while crying there are no wards.
The trench is deep and the mysteries are fascinating. xD