What am I doing wrong?

Hi,

I've been dealing with this for the past while, and lately it's been getting me down again.

I've had several different friendships over the years, but I feel that in so many of them, I'm the main person that texts, reciprocates, tries to make plans, and I always end up disappointing myself when people don't reciprocate.

The apex of it was a 3 day stint shortly after I finished college where I had the following happen:

Day 1: Finished final college exams, and asked the lads if they wanted to maybe go grab lunch or a coffee after (since we were officially done college, I thought it'd be nice to celebrate the end of 3 years together). Mentioned this to 5 people a day in advance (our exam venue was also directly beside the place I suggested, like less than a 20 foot walk). I got 1 response who changed his mind later that evening, nobody else acknowledged it at all, and everybody basically immediately ran off as soon as we finished our last test.

Day 2: Had mentioned plans to a distant friend I hadn't seen in years (was my best friend growing up for years), specifically planning for me to go down and visit him (had bus times arranged, and was staying up at my college accommodation an extra day after finishing to make sure I could head up). Ghosted me a week beforehand when I asked for confirmation that it still suited him for me to head up, still hasn't opened the message 4 months later.

Day 3: Had a big night out planned with a group of 5 lads, again to celebrate finishing college. The morning of (after I had my bag packed, train ticket booked), 2 of them cancelled, and the rest of the lads said there was no point in only 3 of us going out. One of the lads who cancelled called me afterwards to apologise and floated the idea of meeting up, but he never mentioned it again, and even when I suggested a specific festival going on where I live (offering to let him crash at my place), he declined.

Recently, I had another friend cancel on me. For reference, I offered him a spare concert ticket I got cheap, and he initially said yes, but changed his mind a week and a half in advance (tbf, he did at least give me a bit of notice, which I do appreciate). I've messaged basically everybody I know, and nobody can go or wants to buy the tickets (keep in mind I'm already selling them for cheaper than I bought them), so now I'm out of pocket for the price of both of them. I'm just tired at this point, I don't know if I'm doing something wrong, or if there's a fundamental error in the way I'm approaching friendships. Am I doing something wrong?