I sympathise, OP. When a friendship is good and healthy, it's a wonderful thing. But having said that, these days with our busy lives and social media in between, good friendships are hard to find. Don't be deceived by the FB photos, the girls' nights out etc. There's a lot more going on behind the scenes that you don't know. We live in a very image orientated times, and we don't know what is really going on with those people.
Over the years, I've had many friends, probably too many, to be honest. And I lost touch, for various reasons, with lots of them too. Looking back, my 30's were the most stressful times because of that. It left me quite depressed and anxious as well.
Friendships are good, but they can drain you too if you don't manage them. I find it very hard to have groups of friends, and by far, prefer closer one to one relationships, as there's a lot gossiping and backstabbing in groups.
Lately, I only have about 4 good friends on top of my list. People who I feel really comfortable with and trust to a great extent. and then people who are friends but I don't expect a lot from. So if they decide to go and live abroad and I don't hear from them in ages, I'm sort of prepared not to be too hurt about it.
Lately, I realise the days I enjoy the most are the people free days. Going for coffee on my own and reading the newspaper is bliss to me. Maybe because I'm in my 40's now, I really enjoy my own company and a drama free life. So my advice, OP, would be to open up to people a bit more and make more of an effort to initiate contact, but in the meantime enjoy your life as it is too and count your blessings that nobody is talking about you and your family behind your back.