Aw TA, I'm sorry your family aren't being supportive. No-one wants to leave their baby, and i don't think you need him making you feel guilty, as I'm sure you are probably struggling with lots of those feelings already. Tell him to fark off and mind his own, if that's not too blunt!!
My sister went back to work when her DS was 13 weeks cos that's all the maternity leave you got nine years ago. I was supposed to go back when DS was 18 weeks, but sold my flat, lost my footing on the property ladder and squatted at my folks for six months before getting a council flat, just so I could take two years out. We do what we have to to get by.
Just remember though that after you've gone back, we'll be here to keep you smiling
Can I send you some virtual {{{{{{{{{{{hugs}}}}}}}}}}}}}}
xx