My team has the worst record (3-9) in the league and has the most points
QB- Ryan
RB- Charles
RB- Martin
WR- VJax
WR- Marshall
WR- Bowe / Moore
Flex- Spiller / DMC
TE- Rudolph / Hernandez
D- Texans
K- Bryant
With the exception of Brandon Marshall and to a lesser extent Doug Martin,
your entire team is boom/bust. That's what happens when you have a team like that. You put up huge numbers some weeks, but other weeks you struggle.
Welcome to fantasy football
Not sure what this means (other than you trying to be snarky), but it's obvious to see why you lose pretty regularly. You have players who are just as likely to give you a big 30+ point game as they are to give you a 3-4 point game. Here's an example, using your team.
You have Jamaal Charles. Another team has Frank Gore. In the total points for my PPR league, Jamaal Charles is averaging slightly more points than Frank Gore on the season, but the person who owns Frank Gore is more likely to get consistent week to week points than you are, because you have a boom/bust players.
You happen to have a lot of players like that. A good fantasy team has a healthy mixture of boom/bust options with consistent week to week performances. Your boom/bust players outweigh your consistent performers by a large margin. There happens to be a team in my league that is one of the top 2-3 scorers, year after year...but he always seems to miss the playoffs. He constantly talks about how he is the most unlucky player in the league, but in actuality, he regularly builds teams that look much like the one you have. He has yet to figure this out, but maybe one day he will.