Ssh – Printing on a local printer from SSH remote session

If when you connect back to your local it allows you to login before hanging, then this isn't the answer. If you don't get that far, you're probably not getting back to your Mac (either not getting anywhere or hitting SSH on a gateway). Try a reverse tunnel (it will require GatewayPorts set to On in sshd_config on your server, but I believe this is default):
you@yourMac$ ssh -R 2000:localhost:22 user@remoteserver
That should allow you to connect to the server as normal, but also open a tunnel so that you can connect back on port 2000 (any port over 1024 should work), so you@yourserver$ ssh -p2000 user@localhost

EDIT: Changed hostname to localhost

Use an ssh port forward with a backgrounded commandless ssh session:

$ ssh -N -f -L 5433:localhost:5432 remoteserver

with which you can then use:

$ psql -h localhost -p 5433

psql commands like \o, \i, etc will refer to files on the local computer.

If you're trying to do this for scripting purposes then you probably want to use ssh's -n option and a passwordless ssh key with options set in authorized_keys to prevent a shell from being spawned so all you can do is port forward a given port. This is very important for security when using passwordless keys. ssh-agent provides a somewhat more secure alternative but it's clumsier for scripting. Remember that your script will need to record the process ID of the background ssh session it spawned and kill it at the end of the task. It's sometimes easier to use shell job control rather than ssh's own daemonize mode; that way the shell keeps track of the process backgrounded with & and it can be terminated with kill %jobid. See bash job control. (You need to background the port forwarding ssh session so that execution of the script can continue and run psql).

For interactive use you can just invoke the remote psql over ssh, in which case commands like \o, \i, \copy, etc will refer to files local to the server you ssh'd to, not your local computer:

$ ssh remoteserver psql

This works for scripting purposes too, but is somewhat less secure than doing port forwarding since psql is a pretty powerful program that lets you read and write arbitrary files, spawn a shell, etc. You can't really limit what a passwordless ssh key can do if it's allowed to remotely invoke psql. On the other hand, it's a lot simpler to write:

ssh remoteserver psql <<'__END__'
BEGIN;
INSERT INTO blah(a,b,c) VALUES (1,2,3);
UPDATE otherblah SET x = 99, y = 912;
COMMIT;
__END__

than to muck about with background ssh sessions. Really it depends on what your priorities are.