Ghost Blog & Mixed Active Content - nginx

Question

I am trying to publish a blog using Ghost behind a NGINX reverse proxy. However, I am facing 1 small problem which means that content such as images cannot be loaded on blog posts. After looking in development tools, I noticed this is due to Mixed Active Content (HTTP requests instead of HTTPS) being loaded. An interesting note is this works absolutely fine on mobile devices as they do not block HTTP content.
My ghost blog is setup as http://blog.jamdoog.com because a https://blog.jamdoog.com address causes infinite redirects. In addition to this I am unsure how I am meant to create the reverse proxy file's for the HTTPS aspect.
The setup I am using is a reverse proxy with NGINX for Ghost and then a second reverse proxy on "edge" nodes. This is so that I can distribute my content to servers that are closer to the viewer.
I have attached a diagram of how my setup works and my NGINX config files.
Image of web content being served
NGINX config on blog server:
server {
listen 80;
server_name blog.jamdoog.com;
root /var/www/ghost/blog.jamdoog.com/system/nginx-root;
location / {
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header Host blog.jamdoog.com;
proxy_pass http://127.0.0.1:2368;
}
location ~ /.well-known {
allow all;
}
client_max_body_size 50m;
}
NGINX config on edge server:
upstream blog.jamdoog.com
{
server blog.jamdoog.com;
}
server {
server_name blog.jamdoog.com;
access_log /var/log/nginx.access.log;
location / {
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Real-IP $remote_addr;
proxy_pass http://IPOfBlog;
proxy_set_header Host blog.jamdoog.com;
client_max_body_size 10m;
client_body_buffer_size 128k;
proxy_connect_timeout 90;
proxy_send_timeout 90;
proxy_read_timeout 90;
proxy_buffers 32 4k;
proxy_cache proxy-cache;
proxy_cache_valid 200 302 30m;
proxy_cache_valid 404 1m;
proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504;
}
location ^~ /ghost {
proxy_ignore_headers Cache-Control;
add_header X-Cache-Status $upstream_cache_status;
}
listen 443 ssl;
ssl_certificate /path/to/fullchain.cer;
ssl_certificate_key /path/to/the.key;
include /etc/letsencrypt/options-ssl-nginx.conf;
ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
}
server {
if ($host = blog.jamdoog.com) {
return 301 https://$host$request_uri;
}
listen 80;
server_name blog.jamdoog.com;
return 404; # managed by Certbot
}
Thank you.
EDIT: To clarify, I am asking help with a NGINX config to allow me to use Ghost with SSL by default as proposed to redirecting to HTTPS. This would fix this issue.
Alternatively a way to make ghost utilise relative paths.