I'm not over 50 yet

but I have found it's definitely harder to make close friends as the years go by.
I meet people who seem to think it's easy to meet people but they are usually married or much younger. They forget that they met their spouse while they were in college, etc., meaning, when they were surrounded by lots of people their age (usually single), saw them on a regular basis, and didn't have as many responsibilities, such as a mortgage, family, insurance, vehicles, etc. No one has the time or interest to make just a plain old friend. Most people, as they move into the adult world, find that all their time is consumed by work, family, and maybe even church

with nothing leftover for anyone else.
When I go to churches, I am always in-between. At my current church, there is a group for 55's and over, as well as for 18-30-year-olds. I have a hard time relating with either extreme, but usually go with the younger because I find more that I can relate to in that group. However, the group I now attend is all couples and a few single girls who all have their own cliques.
I wish I had some good advice for you but I find myself struggling just as much! I was especially disheartened when talking to a co-worker who is 47, has lived here 22 years, and said they've never made a good friend in this area. Not that it's impossible but I totally get where you're coming from.
In the past year, the only friendships I've been able to rely on are ones from the past (but are on the other side of the country) and some great people I've met on CC.