I'm sorry this is probably going to be really fucking long and maybe a bit confusing.
This post involves swinging, there are lots of different dynamics to swinging relationships so however you think it should work is not always the case. Please don't come at me if you think it's seedy and gross, that's just your opinion and I've heard it all a million times before from people who have no real idea
I have been with my husband since I was 15, and I am now 30, so half my life! He is 2 years older so we're almost the same age. We've been married 6 years. Many years ago, we discussed/fantasised about having a threesome, we decided to try and make it happen so we joined a swingers website and never looked back. We have been swinging for 12 of our 15 years. It's more of a cuckold swinging relationship where I will have sex with other men and usually leave DH waiting for me at home. I usually go to swingers clubs or will occasionally arrange to meet men off the site (but ONLY if they have several verifications from other members so you know they're genuine). Obviously not during the pandemic though, but with just one exception which I'm about to talk about...
Back in 2019, I met a man from the site, we went to a hotel and the sex was incredible, it sounds so ridiculously cliché but it really was like the sex you read about in erotic novels, where you just get totally lost in each other and keep going for several hours. After that meet we kept in contact, briefly chatting every few months (stuff like "Hi, how are you? We should arrange another meet if you're keen?" Etc just really brief conversations of 2-3 messages. About 9-10 months after the first meet, we met up again and it was just as amazing as the first time. Again briefly chatted every so often after this meet. The 3rd time we met was just before the first lockdown, after this, we started chatting a bit more often and we tended to meet up in between lockdowns 
(he was WFH and I'm a SAHM so not like we were constantly mingling with other people so the risk was as low as we could make it, although that does not excuse our recklessness and we've been extremely lucky not to end up ill).
I have met up with him 3 times this year and honestly, I really like him. I feel happy when I spend time with him. He's kind, courteous (he opens doors for me!), generous (sent me an enormous luxury hamper for my birthday!), he makes me laugh, he does incredible things to me in bed and he's just all around lovely. I often find my mind wandering, thinking about him. He has actually said he sometimes thinks of me too. DH knows about all the meets but he has no idea how I feel about him, I'm careful not to talk about him too excitedly or enthusiastically, I don't want to hurt DH by letting him know I like this guy more than he realises. He thinks I just really enjoy the sex. I haven't let on to anyone how I feel, well, apart from you reading this thread now.
Now, to DH. I love him, but I'm not sure if I'm IN love with him anymore. I'm feeling more and more unhappy. Over the last few years he's become increasingly grumpier, mostly with the children, he changes after they go to bed and he's all cheerful and lovey dovey with me. This carries on until the moment he gets out of bed the next day when he flips into bad mood mode again. I find that he brings the mood of us all right down almost every day. He's just so snappy and I don't know why. He can be laughing and cheery one moment, and snappy the next. I've tried bringing it up but he shuts it down and either denies that he's grumpy, or says he is tired. I don't believe his moods are anything to do with the swinging and how we do it, he loves it and wholeheartedly encourages me to have fun. And like I said, his mood disappears once the children have gone to bed.
At home I feel very under appreciated, like whatever I do will never be enough. He's always very quick to point out what housework jobs I haven't done. But if I spend all day cleaning and tidying, he won't say a word on how nice everything looks. I can't remember the last time he paid me a compliment other than 'sexy', I think the last time he called me beautiful was the night I gave birth to our son over 3 years ago. And I DO remember that because I recall being taken aback, thinking how out of the ordinary it was! I never get a general "You look nice today." type comment. Sex-wise, he is good with his mouth and hands but PIV lasts about 3 seconds and he's done, he feels bad about that but won't speak to anyone for help, we don't have PIV sex often because of this but we do other stuff.
I feel like I've painted him out to be this awful person, he's really not. He's always chipping in with doing housework (despite pointing out what I haven't done, he's always happy to run the hoover round, put a wash on, pick up the bathroom cleaner etc), he's generous with money, always buying us all treats like takeaways or going out for ice cream, days out (pre COVID) etc, when he's in a good mood he's so fun. He usually lets me have my own way on lots of things like choosing our kitchen cupboards, the house decor, getting a dog etc.
Those few short hours I spend with the other man, he pays me more lovely compliments than DH ever does. He calls me beautiful, he says he loves my pale white skin, he says he loves my curvy body and that he can't get enough of me. If I ask to meet up he won't hesitate to say yes because "I can never say no to you." I've spoken to two friends about him and they both say it sounds like he likes me, I haven't admitted to them that I like him too.
Now, here is where I'm confused. I love DH but I really like this guy. Am I just latching onto him and projecting my feelings because he's so lovely to me? I know DH loves me but I just feel so taken for granted, I'm nowhere near as happy as I used to be. To be completely honest even before I realised my feelings for this other guy, I was fantasising about how it would feel to leave DH and be single. I regret settling down so young, I wish I had done more, I wish I had lived as a woman on my own. Instead, I became a mum at 20 and have been a SAHM ever since, even if I did leave DH I've no idea how I would manage life without him. I've been trying to get a job to earn my own money, I don't have any personal savings at all, but because I've been a SAHM for so long and from such a young age I'm basically unemployable. Every job application I either don't hear back, get a no thanks because I don't have experience etc and on the rare occasion I do get an interview I don't get it because of a lack of experience/confidence/knowledge.
I just don't know what the fuck to do with my life. I need some guidance because I can't see a way out or a way forward, but clearly something has to change because I cannot carry on like this for much longer :(