Want to use psychology to give your story authenticity? I'm going to start answering reader psychology/writing questions on the blog. If you have a question, feel free to send it to me using the Q&A form on archetypewriting.com.
Disclaimer: The information on this site is provided as general educational information to readers and should be not be understood as specific advice for any particular individual(s). People who are seeking help for "real-life" problems are advised to consult a local mental health professional.
How might my character react to the idea of meeting his partner's parents for the first time and how might his therapist and partner help him become more comfortable?
My character's mom died when he was young and his father was an alcoholic. Stress at work, stress with dealing with a new living situation, and poor communication skills have led to depression. He is now on anti-depressants and meeting with a counselor. He, his partner, and his counselor are working on improving his trust and communication in their relationship. He is going to meet his partner’s parents (who accept that he is gay and are looking forward to meeting my character) for the first time, and he’s worried about the impression he will make! He doesn't know how to act around a "normal" family.
My first thought is -- how is he around people in general? If he's generally pretty good with people, the goal is going to be to improve his confidence and feelings of self-efficacy (ability to handle the challenge) rather than to teach him how to communicate. But you mentioned poor communication skills, so the therapist might talk explicitly about things like eye contact, taking turns talking, that kind of thing. (If the communication skills issues aren't that extreme, then they might just talk about what your character is worried about and how someone might "normally" deal with those situations.)
One way to help someone improve their communication skills, and/or to deal with new situations where you're not sure what to do is to role-play in therapy. So the therapist and the client "try out" different responses to the situation. What to do if x happens, and so forth. It's a way to practice.
It might also be helpful to have the partner sit in on a session so the two of them can figure out (with the help of the therapist) ways to handle awkward moments, ways in which the partner might best support your character. For example, if the character were to get overwhelmed, maybe he and his partner can have a plan to go grab lunch or walk around the mall, just the two of them, to get a little break. The character, his partner, and the therapist can also talk about practical things that can be nerve wracking—for example, what should your character should call his partner's parents (Mom and Dad? John and Jane? Mr. and Mrs.?)
If your character were my client, I would also tell him that it's perfectly normal to be nervous about meeting your partner's parents for the first time. (That might seem obvious, but sometimes just being told that a reaction is normal can make a huge difference to someone.) I would also tell him that it's okay for him to say something like "I'm a little nervous about meeting you because I want to make a good impression." Rather than making you look foolish, that kind of thing just makes you more human, and the parents will probably be feeling some of the same feelings.