Landlord ignores me, leaking roof for 4 months & deposit is missing!! Advice needed..

[Laurieloo2]

I am renting privately with my husband and toddler, we moved in the start of march 2013 and shortly after the roof in the conservatory begun to leak in several places. It leaks pretty easily with minimal rain and has consistently got worse sprouting leaks in new places. I advised my landlord and he got someone round for a quote. She said The quote was "too expensive ad I can't afford it" so thy was forgotten about and instead she said her friend will some to fix it. She said on 2 occasions it would be next week probably on such and such day and each time no one ever came. She never responded to me then I found out via Facebook she had been on holiday for best part of a month (slightly insulting when she can't afford to fix the roof!). By this time the roof had been leaking for 3 months. Now the last month she's had another quote as I kept chasing her and told her of the fire hazards its causing as one leak is directly on light fixing, another on plug switch. Another company come to quote 3 weeks ago, she now does not respond to any of my messages and emails. On another not i have been asking for my deposit receipt for months. In contract deposit is supposed to be lodges with mydeposits.co.uk have checked with them and they have given me written confirmation that my deposit has neverbeen lodged. Again she never replies to me when I request my receipt leading me to believe its in her pocket! This has now been going on for 4 months. i don't know what to do, we are a family on housing benefit so finding another property is no easy task nor raising another deposit & I'm concerned about the legal implications. Any advice would be welcomed.