how to get over missing out on meeting people and relationships

for much of my adult life i have had mental health problems and i missed out on meeting people and having relationships, which when i think about it i find devastating as i can't get those years back, can't get the time back...i'm now middle aged, aged 47 years old.....i just recently joined a dating app on my iphone.

my question here is how can i 'get over' missing out on so much? get over missing out on meeting people and having relationships? is it possible to get over it as devastating as it is?

for much of my adult life ive been alone travelling in a dark void.