OMG my husband is the hugest social butterfly on earth. Drives me nuts when we can't even carve out a Christmas day to ourselves without a million conflicting social scenarios. He's on the road traveling most of the year and when he's home little by little he starts lining up social engagements with our local friends. First one time per week, then several, then every day/ night, up to sometimes several times a day. I'm always invited, but hardly ever want to go. Or he's off jetting to see family or friends all over the country, even if he's only home from tour for a few days. We'll wait months for him to have two weeks off, only to discover he's going to go visit his parents during one of those weeks. Since he travels so much, he knows millions of people and there's always a wedding or funeral or social event somewhere in the nation. No weekend camping trip with old not-so-close friends is too minor or too far away. How many times have I said, "Um no, actually our whole family is not going to fly to your distant twice removed ex step nephew's wedding (who you never met) just because they sent an invitation". Budget never succeeds in holding him back-since he tours for a living he's always got airline miles to cash in and is happy for any couch to sleep on. To be honest, I thought he would outgrow it. 10 years and 3 kids later, I get it. He won't.
The only reason it works for us (and it may not forever-only because I've had to handle every major emergency here without him -which gets old) is that I'm an uber hermit who LOVES time alone and doesn't mind being the one home with the kids all the time. If he's home, and I want to go do something, he always supports me. We trade jobs and favors to make up for all the "going out" time he gets. "OK honey, you can go over to John's and listen to music all night AGAIN, IF you take the recycling and mow the lawn first and then take the kids to the pool. Voila. Work done, kids entertained, whole day to myself, and whatever movie I want to watch while he's gone having man time listening to music and talking about the same mundane alien conspiracy theories all night. He's paying the bills, and I'm a full time sahm "taking a break" after a long FT career (having 3 kids under 5 is a cake walk compared to what my job was like), so I feel blessed and lucky to be doing what I want to do, even if he's not home a lot. He actually gets on my nerves if he's home to much :-0. I'm so conditioned to him going out, if he's been hanging around the house for 2 consecutive nights I'm like, "what are you doing here?"
On some level you have to be OK with it, because forcing him to stay in all the time isn't going to make him a happy camper.
I think you need to draw up a plan that YOU NEED each week including the windows of time and activities you need HIM to do, throw some in for yourself-trip to the store alone, girl's night, whatever and also be supportive of his leisure time in that schedule too. Schedule it all.
If you cant' find ANY common ground, it may be futile, but you can probably improve things by accepting he needs to go out, just making sure he also does his duty at home. If it doesn't work out, you can marry a home body next time around (not trying to be cavalier about it, but some people are social to the extreme).
I know friends whose spouses are ALWAYS HOME, and NEVER do stuff without them. That's a personality type. You can't force it.
Your husband doesn't sound that extreme actually. I bet you can find some middle ground.
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woops, just read your update. these problems are bigger. You need to be happy. Good luck working on this, the dishonesty and disrespect is not OK. He's making you feel like you're not worth the effort. You may want to let him know he's not trapped if he wants a separation and wants to move out and see how he takes it. Right now, he feels you trying to get him to comply with your ways. It' not wrong, but it never works if he has different ethics and priorities. Maybe if he knows he could lose you, he won't be playing so hard to get. Best wishes, I'm sorry you're going through this.