Friend that makes excuse not to hang out!

Hi,

I have a very close straight friend who I came out to 2 years ago and since then we have grown to be closer as he was more than accepting. We see each other every single day as we work together and extends to outside of work as we are constantly texting each other, not to forget messaging each other all day long on social media platforms. According to him he considers me to be one of his best mates.

The issue here is whenever I try and make plans for us outside of work to hang out, he either ignores the message or makes up excuses. The latest was today when I asked him if he wants to go for a night out at the end of this month, he didn't open the message for a whole day (unlike him) then when he did, he said that he's not sure because he is already going out three times this month and he'll end up short of money, then changed the subject. Mind you he is always out on nights out with his other mates.

I am now overthinking if he feels uncomfortable going out alone with a gay friend even though I made it clear to him on a previous occasion that I have no interest in him whatsoever. My mannerisms are not camp as I am still in closet and "straight acting". I am not sure where to go from here.

Thank you