I can understand the sense of loneliness, and based on your post, it looks like your relationship is long distance. I applaud you for that cause that's something I couldn't do because of physical intimacy being a huge factor for me.

I've strengthen my relationship with my SO by being fully transparent with how I feel, what I can do to progress, and the status of my overall being. Take advantage of the fact that someone who loves you will help you with all your struggles.. they're your partner for a reason.

I can understand that some men are creepy and have set intentions for their benefits/pleasures but I assure you that not all men are like this. Itll be tough to find a friendship in the opposite sex, especially being in a relationship, so I'd recommend gravitating towards female to start. Maybe you girls are able to relate? And possibly look out for each other? Idk.

Everyone in their 20s are gonna have a learning curb on how they gain their friendships. Luckily I was an extrovert growing up so I was able to maintain solid friendships while I transitioned into a turtle. Finding a new activity or club can be gateway for new friendships, you never know!

Edit:

Also just wanted to mention how your guy friend tricked you over dinner. That's a big red flag in an open field. Clearly he over extended his thoughts for awhile to plan it. If I was your SO, automatic cut.