How long should I leave it?

Unfortunately I've had a miscarriage with my first pregnancy and both me and my husband were devastated. You hear of this happening to other people and never think it will happen to you. Now every where I look all I see is pregnant woman and tiny tiny babies. My eyes are automatically drawn to all the baby clothes and toys and I can't help thinking that it should be me shopping for all these things and enjoying my pregnancy. Everyone keeps telling me everything happens for a reason and I totally agree but it just doesn't make it any easier. How long do you think I should wait untill I try for my rainbow baby? I'm so desperate to be a mum.