How can I be more open with my partner?

Im definitely a loner so I’m used to dealing with my problems all by myself. If I’m feeling down I deal with it by myself. I literally walk out the room, cry then come back smiling. I recently lost my father and Ive only cried in front of him once and that was because I was in the car on the way to see my mom right after I found out. I can’t open up to him and honestly tell him how I’m feeling. I feel awkward even bringing up my emotions or.. anything for the matter if I’m not asked. I want to feel close to him.

Has anyone gone through this and overcome it?

If your partner asks “how’re you?” Do you just said “I’m good” even if you aren’t?