Hello K713 & welcome
Reading your post, let me just first say that I am so sorry for your loss.
It can be difficult to explain to people or talk about as openly as you might like, all of the emotions and bonding, which you mention, that a person goes through when there is a loss of this magnitude.
I suppose there are support groups and counseling, but sometimes you really just want people who are close to you or that you care about, care just as much about you and what it is you're going through. Sadly that isn't always the case, however.
If your friend has moved on, it may not have the outcome of support you're hoping for. But, given this experience and the bond that WAS
created, as strong as it was, you could take that bond with your "peanut" and see if there isn't something more to it, such as actively pursuing either having a child or focussing on a a relationship with a partner that might like the same thing.