sex after baby

I'm 4 weeks PP and I know at 6 weeks my bf will be pushing me to have sex again (can't blame him) but I have never felt more insecure in my life. I know my vag is way looser and I just feel all gross and flabby. I wanna cry when I think about having sex again and just about my body in general.. How do I get over this? I don't know how long it will take to feel normal about myself again.