Going insane.. Anybody else in this position?

So.. I have been trying to conceive for about 2 years now.. It never happened i feel like shit... I have been pregnant before but i miscarried that was in 2010 .. I know i can get pregnant ..but i gained a lot of weight i used to be 130 now i weigh 240.. Now my periods are never regular... I will go months without a period and sometimes have my period for 7/8 days .. And then next month i will be spotting .. Its like a rollercoaster its crazy... I have no idea when i will be ovulating it is so stressful plus i was told i had an under active thyroid.. But they say its under control now.. But i doubt it .. Is it my weight gain? That has my period out of whack... Anybody else in this position? What do i do ughhhhhh i want to have a baby so badly.. And its just not happening we have sex literally every day ... And still nothing ... I need advice.