I feel like I can't be alone

For so long, I've felt so unhappy whenever I'm without a male partner. I've considered the usual "learn to be happy with yourself", but it just doesn't feel the same. I know how to be happy with myself, but it just feels like something's missing.
Whenever I'm alone I think about past relationships, hook ups, and everything in between, especially the most recent one, which was an in-between. Long story short, it ended abruptly and without any sort of closure, which has left me wondering. I've considered texting him, but last time I saw him was like 3 months ago and I don't want to embarrass myself. I even woke up an hour ago from a dream that involved him, which made me feel like I should try to talk about this.
Then, to add onto this, we're all stuck in quarantine, which is to say, we're stuck with family. And that just drains me. Being solely surrounded by people that bring up a new issue everyday makes me feel that mine aren't as important and don't need to see the light of day. I have realized that when I'm with a guy, I'm happier because he makes me feel important, so maybe the issue's as simple as that, but it doesn't seem like it.
I look for solutions where I shouldn't be, mostly in heightened experiences, so weed and drugs like it. I know I have no addiction to the substance, but I'd rather not have the thought process of "Not feeling good today? Just smoke a little tonight." The presence of it just makes for an easy getaway.
I don't know what I'm looking for here. I can't expect an answer to all my solutions, I just felt like I needed to vent this out somewhere.