Is it bad for cats to be kept outside all of the time?

My cat was originally dumped in my yard along with her kittens who i re homed. We really bonded and I have kept her despite the fact that i m a student with a very low income,renting in share houses and it can be very difficult to find cat friendly houses! Unfortunately we have been evicted due to our house being sold, and i have been desperately looking for a place for me and kitty but with no luck! With only two weeks to go i have been offered a sublet at a friends house but she has a new baby and will not allow my cat inside the house. I m really running out of options so i have to consider this. There is a big backyard but i m still worried about it as she has been an indoor/outdoor kitty up until now and i will really miss cuddling up with her. In terms of whats best for her i m wondering, should i be looking to re home her if i cant find any option for housing other than this? how bad is it for cats to be outdoors all the time?