Play Minecraft cost-effectively for two?

I would like to play with my girlfriend on a Minecraft Map, have you read that Realms is there an inexpensive / free way to play together?

Aternos for example

Thank you, but google not sure

If you can meet, you can just share your game in the Lan and she can join.

Alternatively, you can make a craftbukkit / spigot server, which will not last long, especially if you do not install any plugins

You could also just host a normal Minecraft server yourself - it's free.

Instructions are also sufficient.

Go to Aternos.org, there's free servers, just wait until it's started, but it will not take long

It's safe, I use too

And how exactly do you take that? Aternos is completely safe

If you want I can provide you a server.