Should I start a new life with a new lover

[drobs]

Actually now, BIL, I think you're not only involved in a love triangle but in a love square, in which you have two male lovers (one on the way out, one still trying to make his way into your permanent life), and one woman in one corner....

I missed that H has a live-in GF.

I got a rule about dating guys that are bi, married, or in a relationship;
it's not worth my time, emotions, and feelings.

I deserve someone that wants me and only me.

The sex may be great, but I deserve the whole package.

As the old Saturday Night Live skit goes...
"I'm good enough, I'm smart enough, and gosh darn it people like me."

[AlaricXY]

Sounds like you're caught in a love tornado between two hot guys, BIL.
Do what's best for you, man.
But I have to say, after years of relationship with M, you must take that into consideration. Don't you find it to be a pity if you leave him after years of love and happiness? He might be rather settle at 40+ and calmer, wiser. However, no matter how attractive he is, he is rather mature, and should guys hook up with him, it might just be for sex. I mean, why choose a leftover appetizer when you can have a fresh one? Normally, we like our partners without a too wide age gap.
If you ditch M, M would be devastated for he loved you all these years, but now you no longer feel the same about him. My feelings would be hurted if I am M.
You must consider his feelings, BIL. If you really love him, give love another chance. And start your relationship with him on a fresh sheet with your problems solved.

About H, I suggest you maintain a 'friends only' relationship with him for now.
Should you and M seperated even after trying to get back together, at least you know you didn't really cheated on M with H.
If H really likes you, he would respect and love you, coz loving someone does not mean owning him at times.
You need to know, you like H, coz of he's sexually attractive or you really like him?
At times, men think with our dicks instead of our brains.

Coming from a place where homosexuality is oppressed, you are lucky to find true love with M and met a great guy like H. It is nearly impossible for guys here to have LTR with each others.
In a way, we are all searching for love, to fill the void in our soul, and you are lucky to find one. Not all of us have such luck like you.

Do what's best for you, mate.
And follow what your heart says.

[Dimdim]

Well I believe you should fix things with M if you truly love him. What you are doing right now is cheating and not being faithful, thats so wrong in my books. You either end it or stop doing what you do. Imagine someone doing that to you how would you feel? Theres ups and downs in a relationship and everyone should try to fix things theres always a way. Seems like you've just given up on that.

[marshlander]

I'm sorry to hear that things have gone sour with your partner. However, he does seem to have been a rock in your life. You met the new man, who is supposedly in a relationship with a woman, in a sauna. Doesn't that beg questions about the way he views commitment in relationships? If you follow him into new pastures there may be things you need to discuss.

I'm aware that my own history of working through coming out and changing my life may not qualify me to offer advice in the straight fidelity department.

[Paul1]

I agree with marshlander, tread carefully, here be dragons. If you separate with M, I wouldn't tell him you're seeing another guy, it would only make it harder.

[warmpixels]

Get to know yourself... what you really want out of life and where your goals lie.
Find out a bit more about the root causes of the problems between you and M.

That should take a lot more than a few days, and you really shouldn't let yourself think too much about the whirlwind romance with H.

Get to know a lot more about H... do a background check. Find out his levels of commitment. There's plenty of good advice from the others. I think if you don't take any snap decisions, everything will happen quite naturally.