What should I do?
Encourage him! Yes, exactly that. Encourage him and support him, even though it seems that you are the one needing support. Remember that you are now a type of security, a framework for his life, because of you he can confidently explore new loves with the knowledge that you are his rock. He can go farther, be more daring, and he will come back to you with more confident and grateful for your support.
Basically, you need to continue as usual, without complaining on a daily basis and definitely without punishing him. You can, however, set red lines. For example, have a serious conversation when you both have enough time to speak, without stress, and decide that you will go out together at least once or twice a week (assuming you used to go out more often), otherwise your relationship will lose significance.
As a polyamorist, you should expect your partner to share with you, at least in general, the relationship woven with his new partner. When the time comes when you meet a new partner of your own, you will tell him about it.
In order to cope better with the love of your new partner, you should learn about the three love mechanisms in the brain: lust, romantic love and attachment.
❤ I suggest you read the article “Why do men and women cheat?” if you have still not read it.
I assume the relationship with your partner is at the attachment stage, that is to say you have been together at least one year and you love each other over and above sexual desire.
Lust
When he meets a new “love”, he first fulfills his lust, satisfying a sexual need he does not get from you, for example a BDSM session or a different kind of sexual fantasy. (Don’t be hurt by this. We polyamorists are aware that we cannot satisfy all the sexual needs of our partners. For example, if your partner fantasizes on sex with a Thai ladyboy, this is not something you can or want to fulfill. If she wants to sleep with a young black guy, this is not something you can offer). If the need arises, then after a short period of several days or weeks, after the need has been satisfied, he will return to you happy and content, ready to give you much more love than before, and there is also a chance that the sex between you will improve.
Note: If you or yours are only after a one-night stand, it is not necessary to advise the other party that you are polyamorous (or married), but it is mandatory to inform your partner that you are having sex outside of your relationship (ensure that your partner uses protection and carry out tests for detection of sexually-transmitted diseases at least once every six months).
Average time: several days up to several weeks
Annual average: 0 – 10 sexual encounters – these are most of the partners your partner will meet (for men the average might be higher).
Romantic love
It is possible that your partner will fall in love with his new partner. This process will be longer, and you will feel, at least for a while, changes that will (detrimentally) effect your relationship. After the falling-in-love stage, your relationship will probably return to be what it was. (Your partner must advise his new partner that he is polyamorous as soon as possible. You have the right to ask to meet her. If your partner refuses, he is probably hiding something from you, be careful!)
Average time: several weeks up to several months
Annual average: 0-3 fallings in love
Attachment
If his new relationship continues for more than one year, he will reach a level of attachment, which is deep and stable love not based on sex, though it includes sex. At this stage the relationship with your partner should be stable and loving. If this is not the case, talk to him about it.
Average time: at least one year
Annual average: 0-1 loves per year (usually 0, because polyamorists have 3-4 simultaneous loves at the most)
In conclusion
Usually the affair with the new partner will end after your partner has fulfilled his lust or romantic love, which means that your relationship will return to the previous situation within several weeks or months. In the event that your partner gets attached to his new love – congratulations! This is polyamory ?
By then you will have known whether his new-old partner continues to be secondary or becomes primary (which changes your position).
During this period, it is likely that you will meet up several times with his partner, and you may like her. You might have sex together (ménage à trois) and even live together in a kind of commune.
Could my partner’s falling in love cause him to leave me?
If the relationship with your partner is not sufficiently deep, and at the same time his new partner gives him a higher value and cancels out your value, it will only be natural that the intensity of your relationship will decrease, which might lead to separation. However, this only testifies to your incompatibility. In the long term you will both gain from the situation; eventually you will get to know a partner who is more compatible with you, instead of staying with someone who is incompatible and dissatisfied with your relationship.
If it could lead to a separation, then why get into a polyamorous relationship in the first place? In monogamy I can keep my partner.
Let’s be accurate: you do not keep but rather imprison your partner. At the end of the day, both of you are stuck with each other for better or for worse. It usually starts out well, but after several years the less good aspects rise to the surface.
And what if I like being imprisoned? Then remain in a monogamous relationship. There is nothing bad with that, if both of you choose it and both of you are happy. Polyamory does not suit everyone. (I witnessed how my parents had a loving monogamous relationship their entire lives. It is definitely possible).
What I can say about polyamory, which cannot be said about monogamy, is that I know that the partner I am with loves me because she is with me of her own free will, and not because she is forced to do so due to marriage.
Let me ask you this: if your partner has no option of loving someone else, is your love genuine?
Now it’s your turn: Start here to search for you new loves