Internal load balancer and loopback access from VM

I understand I can not access LB IP from VM behind it. My question is what would be the solution to my problem.

I need internal LB which will load balance traffic on TCP port 25 accross 2 VMs (SMTP relay servers). This was fine for everything on internal network except for machines themselves which need to relay SMTP as well via that VIP.

What can be done to rearchitecuture environment so I can have my entire Azure infrastructure to be able to relay through that VIP?

Thanks,

G