Piecing - H still contacts OW

[ourcrisis]

I have not posted for a long time. Time for some update. I know some of you do care and I appreciate that.
We moved back to our home town. So one thing for certain, H is not having PA. To h, this is "decided enough" for him to show that he wants to be with me. These few weeks, we both tried to be nice to each other. We go out on dates, I tried to invite old friends out to reconnect and it's helping somewhat. It is good to hang out with old friends that we have not seen for a while. The bad part is one of our best friends are going through difficult times, on the verge of D. So I am not sure seeing them having dinner with us but not talking to each other helps or not. It helps to see that we are trying while they are being miserable. OTOH, it may plant thoughts into H's mind that D is not so bad.
However, H is still in contact with OW via phone, txt, email, etc. So there is EA. We had another argument/talk last night. I asked him why he couldn't cut off contact with OW if he already decided to be with me. From the conversation and assuming H is telling me the truth, he is very afraid to cut her off totally because she is in depression. He is very afraid that she will commit suicide because he is her only emotional support now (she has no close friend to talk to. A is a secret). H is still telling her lies (that he will be there for her). I don't know how OW can still believe this when he packed up the whole family and moved so far away, ignore her calls when he is with me/at home. Is she that lonely/desparate that she will hang on to anything?
I asked H about D. He said he does not want to unless "he have to" (guessing if she threatens suicide or some other threats he will "have no choice" but to leave me). I asked him if he has a timeline to cut off contact. He said he does not know. Upon further probing, he said soon she will call him bluff (on being there for her when he shows no sign of moving, or further action). Then I am guessing H hopes that she will just back off and live her life without him.
I am torn between two choices. Do I let him continue this EA, hoping all he told me is the truth and hoping that OW will leave him alone after a while (when she is no longer in depression, or find another friend to talk to?), and continue to date and have happy times with H, ignoring EA on the side? OR, do I just tell H to back off from me (He's been very nice to me, taking my occasional temper and nastiness), until he cuts off all contact with OW? I am leaning towards being nice and build happy memories with H now and wait for him or OW to make a move to end this. At the same time, I am so afraid that if H cannot be strong enough to just cut off OW, do we have a future? This may happen again with another OW, or with the same OW years down the road when our M turns rocky (according to H, our M was always good so if A can happen when things are good, how about when things are bad?) Will he be strong enough to resist another A later?
Lots of thoughts are in my mind right now. Seems like H wants to be with me but just cannot cut off OW. How long can I wait for this to drag on? My love tank for him is decreasing every day.
I don't know how long I can tolerate this.