Hello Namastnae, welcome to the forums and for very sorry about what is happening with how your partner is feeling who has been medically discharged from the army.
It's not easy living with someone you have fallen in love with who has finally been known to be suffering from a mental illness because this can create tension, uncertainty, troubled emotions and big changes in how people look at their lives.
The concern is that as he was medically discharged his understanding could possibly be that none of the medical staff were able to help him and now believes the same may also happen with different medical professionals, however, they all approach, not only the topic, but also with each individual and can't be deemed as the same.
It's good you are looking after yourself but your own confidence is disappointed when you arrive home, but we need to rely on our doctors to be as pro-active in our concerns as possible and to be caring, appreciate what may happen in the future and relate to how we are thinking.
If this current relationship has no spark and no reaction from what you may say from time to time and not any sign of intimacy, then you may decide to separate, and I say this for your own protection.